Immortality Begins at Twenty

"Despite what the math says, elves do not gestate for an entire decade."

— Things Mr. Welch Is No Longer Allowed to Do in an RPG "#1616"

Sometimes being immortal or a member of a really Long-Lived race means that aging occurs naturally or rapidly until a character physically reaches their mid-twenties. At this point their aging stops and they get to be young and beautiful forever, or at least a very long time. Sometimes this is explained as the character being immune specifically to the degenerative effects of aging (sometimes as a side-effect of a Healing Factor) whereas growing isn't affected; other times they acquired their powers at a late stage of puberty.

This is a common feature for elves, even if they aren't technically immortal but are just long-lived. A character that's Younger Than They Look may fall under this if they weren't artificially created; sometimes a character looks like a teen or young adult but is only chronologically in the single digits of age, maybe even Born as an Adult.

With live-action productions, this is often used because there is an unavoidable upper limit to how long a child actor can play a given role before noticeably aging, but a good makeup department can cover up evidence of aging in an adult actor for years.

Contrast Proportional Aging, Age Without Youth, and Not Growing Up Sucks.

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Examples

Anime and Manga

• Zigzagged in Bleach: Pluses appear to live much longer than humans, but how they mature and age seems to vary arbitrarily. Rukia and Renji are implied to grow from children to young adults in a roughly normal amount of time, but then don't age at all over the next fifty years. The epilogue, which takes place ten years after the series shows their daughter who looks to be about eight or nine years old. On the other hand, Toshiro looks like he's twelve and hasn't age at all for over thirty years.
• Blood+: Chiropteran queens age normally like humans from birth, only for their aging to stop as soon as they turn sixteen.
• New Cutey Honey takes place about a hundred years after the original series, but Honey only looks a few years older. Of course, given that she's an android, the fact that she's aged at all is surprising. Possibly justified in that she's a shapeshifter, and may have used her powers to age until her teen years were behind her.
• Black Mage Zeref from Fairy Tail was still a young man in his late teens/early twenties when his refusal to stop researching ways to revive the dead finally incurred the wrath of Ankhseram, the deity that governs life and death. The immortality he gained as part of his punishment halted his aging and granted him Nigh-Invulnerability. Four hundred years later he looks exactly the same.
• Fly Me to the Moon: Tsukasa has this thanks to her father forcing her to drink the immortality elixir he was meant to burn at the top of Mount Fuji on request of the Emperor (the real story behind the Tale of the Bamboo Cutter). As Tsukasa strongly clarifies, she isn't 1,400 years old, she's "been 16 1,400 times".
• Played with in Hellsing. Alucard was in his mid-forties when he died (just like the Real Life Dracula), but has the appearance of a man in his twenties because he is powerful enough to assume pretty much any form he wants. When his full power is unlocked, he resumes his original appearance (complete with mustache), but quickly resumes his usual form (and later the form of a fourteen-year old girl). The artificial vampirization process used by Millenium also restores their soldiers to a youthful state, most notably with Walter.
• Maquia: When the Promised Flower Blooms: The Iorph age normally until they reach around fifteen years of age.
• The Phoenix Saga of Ranma ½ has both versions of this. Usually the bird takes a hundred years to grow up, but if you force feed it enough it'll mature faster.
• Neo Queen Serenity of Sailor Moon stops aging at 22 (as do the rest of her supernatural friends).
• Although Witches in Soul Eater live for hundreds of years, the few young witches we've seen (Angela and Kim) are by all indications the same age as they appear to be, implying witches grow to adulthood as fast a human, then grow elderly extremely slowly. Soul Eater Not! reveals that this has a small degree of Proportional Aging, as Kim turns out to be a few years Older Than They Look. Presumably their aging slows down gradually instead of at an instant.
• Vash and Knives from Trigun aged rapidly from birth (by the time they were a year old, they were physically around 8), until they reached the physical age of men in their early twenties. Nearly a century and a half later, they haven't aged a day since.
• This appears to be how aging works for half-demons in Yashahime: Princess Half-Demon, given that Towa and Setsuna are both teenagers and look their age, while their half-uncle Inuyasha looked no older than them when he was two hundred years old.
• Yona of the Dawn: When a young man drank the blood of the dragon and became the Ouryuu, he became immortal and stopped aging at 17. Since Zeno behaves like a goofy kid and kind of looks like a hobo, Yona and her companions have a hard time believing he really is the 2000-year-old dragon warrior. However, since he was a skinny teenager when he became immortal and can't grow muscle, he's a poor fighter and can be easily restrained.

Comic Books

• Jenny Sparks from The Authority stopped aging at 19 and remained that way for the remainder of the 20th century. Probably applies to some of the other "Century Babies" too, but some of them at least appear older.
• The ClanDestine don't have true immortality, as some of them age — just very slowly. The clan patriarch hasn't aged a day since the 12th century.
• Averted with Cosmic Ghost Rider. Frank Castle was an old man when he was dying after an attack from Thanos. Mephisto came to Frank with a deal to become the latest Spirit of Vengeance and ever since Frank was stuck as a senior citizen when he's not in Cosmic Ghost Rider form.
• Members of the Death Vigil are locked at the age they died, hence James being called "kid" despite having been in the vigil longer than Sam.
• It's explicitly mentioned in ElfQuest that elf children grow up quickly and spend an eternity being physically mature. This applies to the Wolfriders as well, who are technically mortal but can easily live 800 years anyway. It does take male elves about 500 years to grow a beard though.
• Agamemnon, leader of the Pantheon from The Incredible Hulk. Although he likes appearing to people in the holographic form of a very old man with a long white beard, his immortality kicked in when he was 16. His descendants all had their immortality hit as young adults too.
• Invincible: The Viltrumite Nolan Grayson a.k.a. Omni-Man and his son Mark a.k.a. Invincible. Mark's half-brother, Oliver, may fit this trope even more, since his mother's race have exceptionally short lifespans, causing Oliver to age rapidly into a teenager in less than one Earth year, at which point his Viltrumite heritage kicks in and slows his aging process to a crawl.
• In Planetary, main protagonist Elijah Snow is a Century Baby, human beings who were born at the exact moment a new century is ushered in (in Snow's case, midnight of January 1, 1900) and who possess supernatural abilities, near-immortality being one of them. At the start of the series, Snow is nearly a hundred years old but appears to be in his mid-30s. While she is not a Century Baby, Planetary operative Jakita Wagner is over 60 years old yet looks no older than 30. It turns out that her abilities are the result of her being the daughter of a Century Baby whom Snow knew. The children of Century Babies also possess nigh-immortality in addition to various other superpowers.
• The Superman comics have gone back and forth on whether Kryptonians are immortal but no matter how slowly they age in adulthood, they always age normally up to about their mid-twenties to early thirties.
• Martians in Warlord of Mars are very immortal, or at very least age slowly after reaching physical maturity. The female lead Dejah Thoris, is at least 400 years old by the time she meets John Carter, with the prequel series that she starred in taking place many centuries before their meeting, yet she is physically in her early twenties. A few exceptions exist with Issus and Tardos Mors, who clearly show signs of aging, but its possible that they are really that old.
• Wolverine aged normally until sometime during his prime, when his aging slowed down significantly. Stories set a couple hundred years in the future often show him looking like a normal person would at 50 or 60.
• Wonder Woman:
  • Wonder Woman (1942): In The Golden Age of Comic Books, the Amazons of Paradise Island were women from across history who had chosen to take an oath to uphold the Amazons' ideals and undergone training to safely drink from the Fountain of Youth, which stopped their aging. Most of the Amazons look well under thirty despite being well over a hundred, though there are a few who look older like the physician Althea.
  • Wonder Woman (1987): The Amazons of Themyscira have all looked like they're in their twenties since the Bronze Age, as the only "new" Amazon since Aphrodite and the other goddesses created their island is Diana herself.
  • The Legend of Wonder Woman (2016): While most of the Amazons are mortals with average human lifespans, those who gained imortality by becoming the champion to an Olympian like Hippolyta are all young adults in appearance despite being born in the Bronze Age.

Fan Works

• but i wrote the words to the swan song: While Juliet is 13 in the original play, it's implied that she still aged (as she's alive by the end of the play) but eventually stopped, as she has to leave Roberto and Carlotta when they begin to wonder why she isn't aging.
• Child of the Storm:
  • This goes for most deities and immortals. Asgardians, who live to 'merely' over 5000 years old (which is suggested to be their 'three score and ten') age more or less like humans until they're about 20 or so, then stay that way for the next 2000 years — though they do steadily get more powerful. Thor and Loki are both 1500, and look like they're in their late 20s/early 30s, while their mother, Frigga, is 3500 years old and looks like a well-preserved lady in her late 50s, and their father, Odin, is between 5000 and 5500 and looks like a vigorous man in his 70s. It's also noted that they tend to age like oak trees, getting more solid and more powerful.
  • Kryptonians under a yellow sun are suggested by the example of Kal-El I to age the same way, and to become extremely powerful in the process.
  • Derivations of the Super-Soldier serum tend to impart this effect on successful examples.
    • Bucky was active for decades on and off under the Red Room's control (in between his stints as a human popsicle), but has aged so little that it's easy to pass him off as having been a human popsicle/HYDRA trophy and experiment since 1945.
    • Baron Zemo is suggested to be somewhere in his 70s, and is at least in his mid-fifties. He's also a low-level Super-Soldier who moves like a man in his prime.
    • Natasha was a recipient of the Infinity Formula, which is believed to render the subject immortal (Word of God has implied that it's 'just' a really, really slow ageing process). She's about 80 when the story starts, but is frozen in her mid-twenties, when she received the Formula.
    • Alison Carter, daughter of Peggy and Steve, looks like a well-preserved Silver Vixen in her late 40s, despite being in her early 60s when the story starts. In fact, this is after she adds ageing make-up, and she actually looks about 28, at the oldest. Her children, Carol's mother Marie, and Jack O'Neill, don't have quite the same effect as the serum is less active in them, but it's implied to have slowed their ageing a little.
  • Wanded and Wandless Wizards, to varying extents. Wanded age relatively normally, but can stay able and vigorous well past a century (e.g. Dumbledore). Wandless, owing to their closer relationship to magic (which tends to make them Walking Techbane), hit early middle age and then don't age very much for the next couple of centuries, remaining in the 'old but vigorous' category at around 300, with the really long-lived examples pushing five centuries.
  • The Sorcerer/Sorceress Supreme and their designated successor tend to have a case of this, as they stop ageing once they take the position. Of course, it's also noted that the nature of the job means that the usual life expectancy is about a decade, if that. Doctor Strange is the main exception, having looked like he was in his early 40s since the 17th century, though in fact, it's actually the 6th century, it was caused by the Time Stone, and he's estimated that he's about 500,000 years old, thanks to a lot of time travel — and stopped counting after he hit 100,000.
  • Merlin is a literal case, being about 1500 years old and looking like 'a scruffy grad student'. He nevertheless has the gravitas to effortlessly command the respect of all around when he bothers to try — this is the only person in the entire story who can get Doctor Strange to metaphorically sit down and shut up.
• Codex Equus: Subverted with the deities of the Codexverse. As a general rule, deities possess immortality, but because their biology is completely different from mortals', they still 'age' by growing in size and power the longer they live, all while becoming increasingly eldritch. Depending on the race the deity takes after (or Ascends from), eldritch traits can range from an increased number of wings, magical hair/fur/feathers made of energy, wing gradients, Holy Halos, and so on. As a result, older deities are incredibly powerful, huge, and incomprehensible to mortals and even young deities, with "Primeval"-ranked deities like the Grand Primevals showcasing this the most. While most deities usually get older the natural way, prodigy deities age faster due to possessing abnormal magic reserves and growth rates... and then there are deities who end up having their ages accelerated through various circumstances, like absorbing huge amounts of magic/energy, eating other deities, or (in Moon Ray Vaughoof's case) re-Ascending by having their core divine nature warped into something completely different.
• Here There Be Monsters: Deconstructed with Billy, Mary and Freddy, who all but stopped aging after becoming the Marvel Family fourteen years ago. Legally and mentally, they are young adults who physically do not look one day older than fifteen. They are not happy about it, specially Mary and Freddy who want to get married.
  The old wizard had told them all that, after receiving the Shazam powers, their aging processes would be slowed to a crawl. The three of them would be nearly immortal, to ensure that the Universe would have three guardians of their caliber for as long as possible.
  The big drawback was that they stayed kids.
  Shazam had admitted once that, if they wanted, he could remove that factor from them and they would age normally. But he had no idea how it would affect their powers in their other bodies. None of them had opted to age, as a result.
  Mary and Freddy had been wanting to get serious for years. But they still looked like kids. It drove Mrs. Bromfield, Mary's foster mother, up the wall that Mary was still a young girl in appearance.
• The Melinda Chronicles is a Highlander crossover and plays with this. Melinda is physically around 19-20 but that's only because that's when she died her first death and her immortality was awakened. Other characters like Kai (physically 33) and Isa/Frostbite (stated several times to look about Sonic's age) avert this since Immortals stop aging the moment they become immortal.
• In Operation: S.O.U.L.M.A.T.E., those that get vaccinated against adulthood virus stop aging at 10 years old.
• Unlike her older sisters Celestia and Astelle, Luna was born a unicorn in Princess Trixie Sparkle thanks to magic put on her mother prior to her birth meant to transform her into an alicorn once she was older. She aged normally until a point. Now she's been in her current adult form for over a thousand years.
• The Reaping of Hatsune Miku specifically averts this with the Reaper's Game; you don't age in the Underground, full stop. Ryuto looks like a little kid, but has been a Reaper for ten years; the next-youngest body, Una, has inherited a sushi restaurant just outside the purview of the Game.
• Averted in Secrets and Half-Truths with the Uzumaki. According to Mito, an Uzumaki's childhood usually lasts for over thirty years. The reason it didn't for Naruto and Kushina is because keeping the Kyuubi sealed drains them immensely, taking them from half-immortal to having a lifespan matching an average human.

Film

• Averted in Interview with the Vampire, in which "immortality" begins at whatever age you were turned into a vampire. Claudia, for instance, was bitten as a young preteen, and is quite unhappy with being stuck in a prepubescent body for hundreds of years.
• Played with in In Time. People are genetically engineered to stop aging at age 25, and continue to look the same until their time — which has become the new currency — runs out and they drop dead on the spot. At one point, Philippe Weis introduces his wife, daughter and mother-in-law, all of whom look around the same age. It's also possible to kill yourself through, say, alcohol poisoning even if you still have years left.
• The Man from Earth appears to be about 33, the logic being that this is when humans reach full maturity (and aging after that is just decay).
• In Star Trek: Insurrection, the magic radiation produced by the planet's rings takes some time to stop/slow the aging process, so when Picard asks a young boy if he's really 75, he's told "No, I'm twelve". It also works in reverse, returning people middle-aged or older to their physical prime upon arriving to the planet. One of the townsfolk who looks 30ish or so mentions that they were an old man when they'd first arrived, and in fact, nobody in town looks older than 40 or so. Picard himself becomes notably more spry and energetic after being in the system for a while, though he doesn't stay long enough to have a visible effect on his age.
• While it's not specified, it's clear that this is partly the case in the Underworld (2003) films. Being bitten by a vampire or a lycan results in either a painful death or turning into the respective creature with the aging process stopped. Those who are born vampire/lycan, however, grow normally until physical maturity, at which point they stop aging. This is why both Viktor (a vampire elder) and Alexander Corvinus (the first immortal) are old, as they became immortal later in their lives.

Literature

• Zig-zagged in The Age of the Five: whilst the White and the Voices stop aging when they are 'chosen' by their respective gods, the Wilds (powerful sorcerers who develop immortality naturally) generally cease to age at the point when they discover the secret. Whilst most of the Wilds are older than twenty when this happens, due to the full emergence of their powers generally happening after puberty, one of the Wilds (the Gull, who is the oldest surviving immortal) is several thousands of years old, but has the body of a child of seven or eight.
• The Belgariad:
  • Sorcerers appear to be immortal. They are humans who grow up normally but, once they hit adulthood, they stop ageing. While they retain youthful vigor, Belgarath theorises that physical appearance will depend on the attitude of each individual sorcerer, who make a subconscious decision to conform their appearance to the prejudices and stereotypes of human society. As a result, because humans tend to assume old men are wise and old women are ugly crones, the male sorcerers tend to appear as old men and the female sorcerers tend to appear as young, beautiful women.
  • Ce'Nedra has Dryad ancestry. She initially grows up at the same speed as a normal human so when she and Garion first meet, they are both fifteen years old. Dryads live for as long as the tree they are bonded to, so Ce'Nedra's cousins are hundreds of years old even though they look young women. Both the Gods and the Prophecy hate the inequality of love-matches where one partner is immortal and one mortal, even if they have to turn a mortal into an immortal sorcerer to ensure such equality happens. Once she reaches adulthood, it's strongly implied that Ce'Nedra will now age at the speed of a Dryad instead of a human, which is why she is destined to become the wife of the immortal sorcerer, Garion.
• In the Black Dagger Brotherhood series, vampires live for hundreds of years. Their transition from "pre-trans" to full vampire occurs at about 25, and they age very slowly after that.
• Captain French, or the Quest for Paradise: The Cell Regeneration treatment, which stops the aging process in its tracks, is performed upon request. Most people tend to do it in their early 20s, although some choose to wait until they're 30 to give themselves a more "mature" look. Since the treatment is not genetic, it doesn't affect children born of CR-treated people. The treatment is reversible, but this is only done to criminals sentenced to Aging. Interestingly, youthful looks are a moot point in the novel, as "biosculpting" has allowed people to "mold" their features to any they wish. This has resulted in worlds filled with women who look roughly the same (with main differences being hair and eye colors). The titular protagonist's choice of his next wife is partly guided by the fact that he finds a stunning beauty who doesn't look like she's been biosculpted. French himself gets weird looks from many people, since he looks to be visibly in his 50s and even has some grey hairs (most people don't even know there's such a thing as grey hair). He got the CR treatment late in his life, as it didn't exist when he was born (21st century).
• In Carpe Jugulum, Vlad and Lachrimosa Magpyr were born as vampires. It's not entirely clear how long it took for them to become late teens, early twenties, but it's suggested they've been that way for a very long time, and will probably remain so. (Since The Mind Is a Plaything of the Body works both ways on the Discworld, it's possible that they'll be that way until they stop thinking like a couple of spoiled brats.)
• In the Commonwealth Saga, rejuvenation, or "rejuve," treatments restore people back to their late teens/ early 20s. Most people appear to undergo rejuve when they're in their biological 50s. There's no limit on the number of rejuve treatments one can undergo, and by the time the series takes place in the 2380s, there are many individuals around born in the late-20th century. In the Void Trilogy, set over 1,000 years later, technology has advanced to the point where people can elect to be fitted with "biononics" that can maintain them at any biological age seemingly indefinitely. Most maintain themselves in their early to mid-20s, but a few keep themselves older, usually when they want to maintain an air of gravitas. For people without biononics, rejuve is still around.
• Done in The Company Novels, where the immortals go through the immortality process from pretty much birth to age 18 and then stop aging. They have to use makeup in order to look like they are still doing so.
• Crest of the Stars has the Abh. Barring accident or illness they live to between 200 to 250 years. From birth to 15 they age at more or less the same rate as a normal human. From 15 to 25 years their maturation slows until they're at a point somewhat equivalent to a lander at age 20 at which point they only age very, very slowly.
• In the Deverry novels, the Westfolk age normally until they reach adulthood, stop aging for 3-4 centuries, and then age rapidly shortly before their bodies give out (so getting grey hair basically means that they have two years to live at best). Opinions are divided if the extra youth compared to humans is better than waking up one day and suddenly knowing, beyond a shadow of a doubt, that someone is going to die soon.
• This is the only drawback in Damon Knight's novella Dio (or The Dying Man). In The Future, humans have genetically engineered themselves to immortality and physical perfection; a Free-Love Future, with levitation and Healing Factor enjoyed by all. However, the way they did it was to lengthen the already long period of youth before sexual maturity, creating an asymptotic curve that never quite reaches the apex. They never mature; that's why they don't die. They 'look'' like Greek gods, but they're actually eternal kids. They're not even teenagers. This helps with population control, but they lose out on experiences only adults or the elderly can have... except the title character, a brilliant artist whose loss of immortality is reflected in his work.
• Justified in Dirge for Prester John. People take their third pilgrimage to the Fountain of Youth at thirty, freezing them in time at that age.
• Dragaera: Dragaerans are immature from about ages 1-70, but are still in fighting shape after 1,000 years. They do get old eventually, but the series is remarkably low on infirm, elderly Dragaerans, so it's not clear how long they last as "old people".^note There have been a few references to some reaching 3000+, that look old-ish; most of them meet with "accidents".
• In Joanna Bertin's Dragonlords trilogy, Dragonlords are humans born among humans but utterly sterile, birth marked, and with half-dragon souls; at some point these dragon souls manifest and the Dragonlord is stronger and more magical than most humans as well as able to transform into a dragon, and from that point on they age incredibly slowly. They typically manifest in the twenties or thirties. In The Last Dragonlord, the Dragonlord mentioned in the title is also called "Little One" because he's the youngest, at six hundred years old. Their leader manifested unusually young, at sixteen, and by this point is visibly old. The little one wonders about just how long she's been alive but doesn't ask.
• The Dresden Files:
  • Wizards age much slower than normal humans, with the oldest members of the cast reaching into multiple centuries. They age normally through childhood and adolescence, with their physical aging seeming to slow down somewhere between their twenties and thirties, effectively stopping between 40 and 200. While it's most noticeable in more powerful wizards, even a relative one-trick pony like Binder is initially assumed to be in his 40s, before his second appearance reveals that he's more like in his 140s. Old wizards do end up looking old, though a 300 year old wizard will only appear to be in their 70s.
  • The extensive cast list gives way to a great number of variances of this trope. Deirdre, a roughly 1500 year old host to a fallen angel, appears to only be in her teens, likewise her mother, while her father, one of the oldest men in existence, has the appearance of a man barely entering middle age. Some younger members of their cult, while still immortal, look to be much older physically than their leaders.
  • Uriel, an immortal archangel, is capable of changing his physical shape to any age, though he seems to prefer the form of a young man.
  • The immortal queens of the Fae are described as young and beautiful, though their Fae mothers are depicted as old and withered.
  • Certain vampires, though, play this trope completely straight, and centuries-old vampires are still inhumanely beautiful. Lord Raith, for instance, is about 2000 and looks like he's maybe 30.

• The Empirium Trilogy: The completely immortal angels all look like they're in their early twenties.
• The Guardians of Time Trilogy: Isabel becomes ageless and stops aging at 18, just the same as her boyfriend Arkarian, who is hundreds of years old.
• In The Hollows, it is implied that witches grow up like humans and age little for about a century after they reach their twenties, resulting in a natural life span of about 160.
• Honor Harrington:
  • Prolong recipients are "frozen" at a different age range depending on which version of the treatment they got: mid-forties for 1st, late 20s for second, and early 20s for 3rd. The freeze extends lifespan to the two to three century mark. It also has the effect of extending stages of development; Honor Harrington herself was a bit of an awkward adolescent, gangly and horse-faced, until at least well into her 30s. Such treatments are new enough during the period when most published stories are set that we don't actually get to see any characters who are 250 years old but look "only" 65 or so, but first- and second-generation recipients of the Prolong treatments do seem to get a prolonged middle age as well as the usual prolonged young adulthood.
  • In "Echoes of Honor", we find out that it also extends non-visible aspects of those same periods. Honor's mother, a second-generation prolong recipient, is about 100 years old but has the body of a woman in her thirties... complete with the ability to still bear children. In the wake of Honor's "death", this is exploited to resolve the issue of succession in Harrington Steading, by having her parents produce a sibling for her.
  • This was subject to a retcon mid-way through the series. In earlier books, Prolong prolonged all stages of development, so that a bridge crewed by 20-something graduates of the naval academy looked more like a middle school class, which characters from worlds without prolong found disturbing. Later, however, it's said that children receive additional treatments so they develop up to their 20s at a more normal rate. The retcon came after several mentions that crew on ships had mandatory birth control implants because, in a mixed-gender environment, sex between crewmembers would be impossible to prevent and was officially tolerated within limits. This, combined with younger crewmembers looking like very young teens or even prepubescents, raised obvious Unfortunate Implications.
• Played with in the third book of The Idhún's Memories. Wina, the goddess of life, manifest herself as a zone where all life thrives, grows and reproduces extremely quickly. Children become adults in a matter of minutes. However, since the main characters are in their early twenties at this point, and the goddess of life causes growth, but not decay, they are unaffected by this. That doesn't mean they aren't affected by the "reproduces" part, though.
• In the Immortals After Dark series, those born with natural immortality remain mortal until they reach the age of peak physical strength, whereupon they become fully immortal and "freeze" as they are. Then they heal perfectly from any wounds short of death, but before then, they can scar or lose body parts permanently, except for succubae, who trade on their physically flawless looks. It is unknown what happens if a human child is turned into an immortal species.
• In Another World with My Smartphone: As Leen explains to Touya, fairies stop aging sometime between their teens and young adult years. She's an example of the former, as she's about 612 years old but looks like a pubescent girl.
• Inheritance Cycle:
  • Dragons grow up within a few years, despite having very long lifespans. They reach maturity at around six months, when they're able to breathe fire. (This is taken to the logical extreme in the film, in which Saphira transforms from an infant to adult in a literal second.) However, they never stop actually growing. The largest dragons can dwarf an aircraft carrier, and they end up sleeping most of the time and living in their dreams in order to preserve their energy.
  • Dragon Riders age considerably slower, but the exact details and rules around are very nebulous. Oromis lived for several hundred years and while he looks old, he doesn't have any normal signs of aging, e.g. wrinkles. Meanwhile, Brom and Galbatorix have been around for roughly the same amount of time — over a century — and lost their dragons, but Brom looks like a regular old man and Galbatorix looks to be in his 40s. Normal elves, meanwhile, also age very slowly due to their race's magical binding to dragons, and can live for hundreds, if not thousands of years without aging. The one exception might be Rhunon, but she is old even by their standards; old enough to know about life before the Riders, and bending over a forge for several thousand years can give you a bad posture.
• In Jack Blank, Revile the Undying has an age spanning millennia, but underneath his mask is only the face of a teenager. He was taken in by the Rüstov at that age and had undergone a radical reformation to transform him into a Super-Soldier who can regenerate From a Single Cell, so he hasn't changed at all in all those years.
• Journey to Chaos: Elves stop aging once they are fully grown because their Seed of Chaos rejuvenates them constantly. Eric notes that Nunnal Enaz looks younger than her mortal best friend despite being older.
• Justified in Kieli. The Undying are immortal soldiers made out of the corpses of dead ones. There weren't a lot of kids fighting in the war (which doesn't mean that they weren't dying in it), and a fully grown healthy adult is going to make a stronger, stabler, more efficient soldier than a child... usually.
• In the Kiesha'ra series, shapeshifters age like humans and then stop aging past 20.
• Kyo Kara Maoh!:
  • While not immortal, Mazoku age much slower than humans, which leads to this trope being tragically deconstructed.
  • Wolfram, who looks like a 15–17-year-old Bishōnen physically, is actually 82.
• The Last Unicorn: Given his physical description, Schmendrick the Magician was cursed with unaging immortality sometime in his twenties, or possibly even his late teens. Word of God puts his chronological age as anywhere between his forties and his sixties.
• Inverted in The Meq. The Meq attain immortality at 12 and lose it when they are ready to mate.
• Mercy Thompson:
  • All werewolves look to be in their early or mid-twenties, no matter old they were when they were turned (either continuing to mature if they were children, or reverting to the appearance of youth if they were past their prime). The only naturally born werewolf stopped aging in his mid-twenties, as well. This is stated to be part of their healing and disease resistance magic.
  • Walkers, the offspring of humans and the animal spirits of North America such as Coyote can live for centuries. Mercy is only in her 20s but she has a half-brother who's also a Coyote Walker who doesn't look any older despite being something like two hundred years her senior.
• Mistborn: The Original Trilogy: The Lord Ruler has dominated the world for a thousand years, and is worshiped as "the Sliver of Infinity" in the Final Empire. He rarely makes appearances, but when he does, people are often struck by how young he looks. He looks like a fit man in the prime of his life. This is because his method of immortality involves compounding his youth to expand it infinitely. He can look whatever age he wants; he chooses to look young for obvious reasons. However, after a thousand years that age is catching up with him, so several times a week he goes to a special room in his palace where he can appear older, to give him a bit more breathing room of youth to compound.
• My Babysitter Is a Vampire: Naturally-born vampires age normally until they reach a certain point, which varies depending on the individual. Vincent Graver, the titular vampire babysitter, was sixteen when he stopped aging. Subverted with his younger brother Grebiv, who stopped aging when he was just three.
• A Nameless Witch has the title protagonist cursed to be born undead. Upon turning eighteen, she stops aging and is cursed with eternal youth and beauty.
• Nightfall (Series): Averted with Vladimir, who becomes a vampire in his thirties. Played straight with Armida and Tristan, who are both turned in their twenties.
• Averted in Night Watch (Series). The Others remain human until they undergo Initiation, involving their first trip into the Twilight, at which point they are able to tap into their magical potential. If they are of a mature age, their aging process is slowed down to a crawl. If they are children, they continue to age normally until maturity, at which point their age freezes (mostly). This applies even to vampire and werewolf children. Inverted in the case of witches, who age to an "old hag" state in a mere decade, although all witches use spells to maintain a youthful appearance. This also applies to their ability to bear children. Once an Other witch is Initiated, she only has a few years to have children, before her body is no longer able to do that. There are potential Others who refuse to undergo Initiation and live out their lives normally (although both Watches agree to keep them and their loved ones perpetually healthy and off the list of vampire/werewolf hunting licenses).
• Night World has a justified example with vampires. Lamia (those born as vampires) age like humans but can consciously choose to stop physically aging at any time (they can also undo this process whenever they want, which is said to have "interesting" results if you've been holding off aging for quite some time). Ash Redfern is considering stopping aging after turning eighteen, though Quinn suggests he reconsider, saying that resembling a teenager forever isn't as great as it sounds (he's been seventeen for around three centuries). The vast majority of made vampires (humans or witches transformed into vampires) resemble teens or even children, which is because most people over twenty don't survive the transformation; their adult bodies cannot adjust and they "burn out".
• In Percy Jackson and the Olympians, when a girl joins the hunters of Artemis, they gain immortality. Once they join, they no longer age. All of the hunters are said to look in their late adolescent and teen years. Artemis says she could appear as anything she wants but prefers to appear the same age as her hunters.
• Red Winter Trilogy: In the epilogue of Immortal Fire, Emi realizes that she has been made immortal by Amaterasu entering her body when she realizes that she hasn't aged past eighteen even though she is chronologically twenty-five.
• Subverted in Ian McDonald's River of Gods — one of the many enhancements given to the so-called "Brahman Babies" is a doubled lifespan. They age half as fast physically, but mentally (or at least legally) grow up at a more-or-less normal pace, leading to apparently ten-year-old night-club owners. A short story set in the same universe points out the rather nasty effect this has on marriages.
• In Riverworld, the entire human race through history over the age of 5 is resurrected on an alien planet at the same time. Everyone is at age 20, and those who were chronologically younger than 20 continue to develop until stopping at 20. There's even a term for them — "Rivertads".
• The Secrets of the Immortal Nicholas Flamel: Joan of Arc was turned immortal when she was a teenager, so she has this. Averted with many other immortals, though. Discussed at one point, when somebody points out that the still adolescent protagonist may want to hold off on acquiring immortality until they were at a more mature age, since otherwise they would be a child forever.
• The Shadowhunter Chronicles: Warlocks age normally like humans until their early twenties, upon which they stop aging. However, their mental capacity apparently has its limits; The Shadowhunter Codex mentions a very old warlock (born before Raziel's covenant with Jonathan Shadowhunter, so over a millennium ago) who is senile, even though she presumably still looks youthful.
• Shellpeople in The Ship Who... are humans who were encased in titanium life support shells at a very young age, and grow up to be Wetware CPUs installed into ships, space stations, etc. They're very Long-Lived with the actual maximum lifespan as yet unknown. Being shelled means they have No Infantile Amnesia and are walking (well, wheeling) and talking coherently under one year of age, and 'graduate' and are considered adults at sixteen. Nancia regards some normal or "softshell" humans who are eighteen as her peers and rather smugly says that with their hormonal complications, it takes softshells longer to grow up than it does for shellpeople like herself.
• Played with in Skulduggery Pleasant: magic is explicitly stated to be the reason for mages' long life spans but the effect it has varies from person to person, Tanith Low looks 20 but is closer to a hundred while China and the Dead Men are between three and five hundred years old and only Skulduggery looks his age but Greta Daple is 200 and looks over a hundred and complains that magic isn't consistent about how it effect the aging process. Valkyrie plays it straight as her magic is only starting to slow her aging down at sixteen.
• The science fiction story Start the Clock by Benjamin Rosenbaum is all about the results of averting this trope. An ill-defined plague stopped everybody aging (and apparently gave immortality as a side-effect). The worst-hit group seem to be the teenagers, since their hormone overproduction didn't stop, turning most into what amounts to bunch of sex-mad orcs.
• Conrad Nomikos, the main character of This Immortal, stopped aging somewhere in his mid-20s. He's looked that age for hundreds of years. He is, however, not particularly good looking. On the contrary, one of his legs is shorter than the other, he has a scarred face and heterochromia (different-coloured eyes).
• Played with regarding the elves in Tinker, who can live for thousands of years. On the one hand, they do stop aging physically at 'young adult', approximately their early twenties in human terms, but on the other, it takes them a century to get that far; a forty-year-old elf is physically and emotionally still a young child.
• Tolkien's Legendarium:
  • Zig-zagged with the elves. Their very early development is faster than that of humans, able to walk, talk, and dance within a year. After that, things slow down, and they don't reach physical maturity until around 50 and aren't considered full adults until their first century. After that, they seem to play the trope straight, appearing young and beautiful for millennia, but they are still aging, just proportionally slowly given that their lifespans are potentially as long as the remaining lifespan of the universe. The oldest elves do show signs of aging, such as Círdan the Shipwright, who at the time of The Lord of the Rings has a long white beard, which he earned by being over seven thousand years old, i.e. he's as old as the existence of the elvish race.
  • Numenoreans, at least the nobility, live two or three times as long as ordinary humans, but remain in their prime for most of it, and then will go suddenly from that to senile decrepitude in a matter of months or even weeks. At the first sign, they hand over their affairs to their children and prepare to receive the Gift of Eru (which lesser men call Death) — or at least, they were supposed to do that. When they stopped, that is when the trouble began...
  • The hobbits, on the other hand, avert this: they live longer than normal humans, but also reach adulthood later (in their thirties — specifically, at thirty-three). For example, Pippin, 29, is treated like a teenager (albeit an older one — more like an 18-year-old than, say, a 15-year-old) and certainly acts as such.
• The Twilight Saga:
  • Human/vampire hybrids age to 17 years old in only seven years, then their aging stops. This is the case with Renesmee, who ages to a little girl in a few months, as well as Nahuel, a hybrid who is about 150 years old.
  • Vampires technically avert this, as humans can be turned in any age, from babies all the way to elders. Still, the vast majority of vampires in the series are young adult beauties, which invokes this trope. It isn't until Breaking Dawn that non-young-adult vampires (immortal children; infant or toddler vampires) are discussed, and then only in backstory.
• Witches and wizards in Uprooted grow to adulthood and then stop. It's mentioned that one of them, Father Ballo, spent forty years illuminating manuscripts in a monastery before someone noticed he wasn't aging. The only indication of their true age is in the eyes.
• Inverted in Sean McMullen's Voyage of the Shadowmoon, wherein Laron is a perpetually 14-year-old vampyre... with acne and a stuck-on beard. It sucks.
• The Wheel of Time:
  • Aes Sedai use an Oath Rod (originally produced as a Restraining Bolt for criminal channelers) as part of their Initiation Ceremony. As a side effect, it makes them "ageless" (essentially, wrinkle-free). It also cuts their lifespans in half, which they don't know until they meet wrinkled (though not ancient-looking) channelers who are over 400 years old. It also causes the eyes to look uncanny, since these apparently continue to age, even if the skin around them doesn't.
  • Channelers who don't use the Oath Rod still experience "slowing", in which their aging process slows, allowing them to live for centuries as stated above. The amount of longevity is proportional to overall power. This begins around puberty, the same time that channelers begin to access their ability, and becomes really noticeable around 20. Nynaeve at one point laments the fact that she'll look like she's in her 20s for several decades, making it difficult to be taken seriously as an authority figure.
• Played with in The Zombie Knight. Reapers can stop and start their servants' aging pretty much as they please, limited only by how old the servant was when they died. Captain Erickson is 30 but looks and acts 10, Octavia Redwater (who became a servant at 14) looks her real age of about 80, and Harper looks 30 but is over twice that. Hector (currently 16) plans to wait until he's in his fifties before having Garovel stop him, assuming he gets that old.
  Garovel: That's actually a pretty common sentiment, though. You'd think more servants would want to be eternally young, but as it turns out, most sixty-year-olds don't want strangers treating them like they're twenty-year-olds.

Live-Action TV

• Alien Nation: In the episode "Fountain of Youth" the Tectonese/Newcomer George Francisco explains to his human partner Matt Sikes that Newcomer and humans age at about the same rate until their early 20s when the aging process slows down significantly for Newcomers. George goes on to explain that he and most Newcomer adults are quite a bit older than their appearances suggest.
• In The Almighty Johnsons, the human reincarnations of the gods receive their powers on their 21st birthday. Olaf is the god of rebirth so he is 'reborn' each morning and thus is stuck at 21 and never ages.
• Subverted in Altered Carbon, set in a future where the megarich can resleeve their Body Backup Drive in another body when they die. Laurens Bancroft prefers to use an older body for the respect an older man commands. However, his children are kept in young and beautiful bodies so Laurens can maintain his role as The Patriarch of their family.
• Becoming Human averts this. Adam was turned at 16 and is stuck as either a schoolkid or someone in a badly-paid school-leaver job forever, since he'll never be able to pass for much older.
• Averted in Blade: The Series, in which the process is different for pureblood vampires and those who were bitten. Those bitten are frozen at their current age forever (although no one appears to have been bitten as a child, so we don't know). Purebloods (those born as vampires), age extremely slowly. The pureblood who is frequently seen, Charlotte, appears to be a teenage girl but is actually around 200 years old. The mature-looking Overlord Rusk is his 600s. It's not clear if the aging stops for purebloods or is extremely slow (the original film shows an older-looking pureblood named Dragonetti).
• In Can You Live Forever?, Adam Savage finally achieves this after a long series of experimental medical procedures using Magic from Technology.
• Doctor Who:
  • Time Lords start out as children, but whenever they regenerate, their new form is adult and sometimes rather old-looking. Although each regeneration also has a very long natural lifespan in itself, so apparent age means nothing.
  • In "The Girl Who Died", the Doctor restores a teen-aged Viking girl named Ashildr to life after she sacrifices her life to save her village. The technology the Doctor uses not only saves her but renders her functionally immortal. By the time the Doctor sees Ashildr again in "The Woman Who Lived", she looks closer to mid-20s, but has been alive for centuries.
• Heroes:
  • Adam Monroe says in the webcomic that he actually stopped aging (at least, he noticed it) when he was about 40. His aging had probably slowed down before this.
  • For Sylar, though, it's justified — he acquired his powers of unaging-ness when he (or the actor playing him) was in his twenties, so it makes sense that that's the age he'd stick at.

• Highlander: The Series both averts and explains this. Immortals are always frozen at the age when they first died, so you can get child immortals, but because immortals also tend to hunt each other down, the children don't last long, so you don't see many... the ones that survive the first few years... tend to be off. Immortals above the biological age of forty also tend to be rare, for pretty much the same reason — those that aren't 'lucky' enough to start being immortal when in their physical prime (20s and 30s) are less likely to last long when other immortals come around with a sword and try to cut their heads off.
• Ice Fantasy: Immortals do age beyond thirty-ish, as shown by Granny and the Ice King looking older than this, but they age very slowly and most of the immortals look roughly the same age. In some cases, like Ka Suo and his mother, parents don't look a whole lot older than their children.
• Kamen Rider fits this trope to the letter, as later teens/early twenties is the usual age range of the lead characters.
  • In Kamen Rider Blade, Hajime is an Undead who lives as a human and thus will never age past his current appearance of early 20s. Highlighted in a spin-off novel where Amane (introduced in the show as a ten-year-old girl) dies as an old woman, with an unchanged Hajime by her side.
  • This also applies to Kazuma Kenzaki, who became an Undead in his early twenties. When he appears in movie special Kamen Sentai Gorider roughly 13 years later, he still looks the part. The spin-off novel brings this to its logical extreme, showing his physically unchaged, but life weary self at the age of 300.
  • In Kamen Rider Double, Philip died at age five and then was resurrected as a stream of data composed from the memories of the Earth. Towards the end of the show, he's confirmed to be seventeen years old, but Delusion Diary #11 hints that he won't age beyond that because his body is made of data. It may or may not be true given that the scene was part of Shotaro's daydream.
  • Kamen Rider Gaim: Played with. The Man of Beginning is still the same age as he was when he became a god. When he assumes his original form of Kouta Kazuraba, he looks the age he would be if he was still human.
• Inverted in The Mandalorian, Mando has a bounty to retrieve an unknown target who, he is told, is 50 years old. When he finally finds his quarry, he finds an infant/toddler of Yoda's species. When he questions this to the Bounty Hunter droid IG-88, 88 reminds him that some species take longer to mature than others.
• Inverted in an episode of Moonlight where a vampire who was turned as a young adult has to spend the rest of his immortal life in the midst of puberty. Additionally, the original unaired pilot had the character of Josef Kostan (a 400-year-old vampire) played by the 60-something Rade Šerbedžija (to give the character some Old World wisdom) before the role was recast to the much younger Jason Dohring.
• The Outer Limits (1995): In "Last Supper", there's an immortal woman who actually stopped ageing at twenty. She explains that she was the last survivor of the Black Death sweeping through her village as a late teenager when she found out that she had a Healing Factor.
• The Stargate-verse has this to an extent with the Ancients. While they (presumably) grow up at a normal rate compared with regular old humans, once they reach maturity they seem to be capable of staying this way for a very, very long time (millions of years if they happen to be encased in ice, as was seen in one episode... though there was limited degeneration, the Ancient in question was still perfectly able to walk, think, and understand modern humans).
• Star Trek:
  • In the Star Trek: The Original Series episode "Plato's Children", an alien race that based itself on Ancient Greece genetically engineered themselves to stop aging at about 30-40 years old. (When Spock informs one of the female aliens that she looks a few years older than the age at which she officially stopped aging, she's a bit miffed, despite being thousands of years older.)
  • In the Star Trek: The Next Generation episode "The Vengeance Factor", the Acamarian Yuta of Clan Tralesta was chosen to carry out a mission to kill all the members of Clan Lornak no matter how long it took after the Lornak killed almost her entire clan. Among the genetic modifications made to her were ones that slowed her aging signifigantly, allowing her to spend nearly a century tracking down the last few Lornak still alive.
  • This appears to be the case with Vulcans in general as well given their extended life spans. The character of Tuvok on Star Trek: Voyager visibly aged in appearance from the 2270s when he was a teenager to when he served on the USS Excelsior as a young adult in the 2290s. However, his appearance changed little from the 2290s up through the 2380s.
• Ultraviolet (1998): Vampires never age past the age when they were turned. Most vampires we see were turned relatively recently, because their interactions with the mortals they've left behind are a major source of the show's drama, but there are a few striking examples including a vampire who appears to be in his 30s but is actually nearly a century old, and another who is an adult with the appearance of a child. According to the team leader, most Vampire Vannabes are recruited when they start moving into middle age. "It's when you start realising that one day it's all going to end. No matter how many times you go to the gym."
• Wonder Woman (1975): Wonder Woman is thousands of years old, but she looks like she's in her 20s — especially since Lynda Carter was in her 20s during the show's run. This is even mentioned specifically in "The Return of Wonder Woman":
  Steve Trevor: You can't be more than 23 or 24 years old.
  Wonder Woman: I will be 2,527 years old on my next birthday.
• In Young Dracula, vampires age normally until they turn 16 years old. From the looks of Dracula, they probably still age a bit after that, but not much.

Pinball

• Matra Magna, the antagonist of Pinball Magic, appears as a twentysomething young woman, though she is Really 700 Years Old.

Print Media

• Averted in a Dragon magazine Zogonia strip, when Kev is trying to chat up an elf, and when she learns he's in his twenties asks if he's toilet-trained yet.

Religion

• In Hinduism, "the age of the gods is always sixteen".
• In Islam, those who enter paradise will be 33 years old eternally.
• Mormons (and probably other denominations believing in a physical resurrection at the Last Judgment) believe that the dead will be restored to appear as they did/would have in the prime of their lives. Catholics believe the same, for the blessed.

Tabletop Games

• Chronicles of Darkness:
  • The book Immortals features a group of beings called the Purified, who became immortal through one of several rituals that involved dying and then coming back to life. No matter how old they were when they performed the ritual, when they come back to life, they always come back in a body that is physiologically in its mid-twenties.
  • Inverted in Promethean: The Created, as mortality begins at twenty — a Promethean who completes the Great Work becomes a human in young adulthood, and can expect a normal lifespan from there on out.
• Dungeons & Dragons:
  • In the Fourth Edition, races that have lifespans greater than that of a human (for example, eladrin) follow this trope, maturing normally until around the age of twenty and staying like that for the majority of their lifespans. Previous editions gave the age at which they reached "adulthood" but no indication of the rate of maturity (which led to questions like, "is a one-hundred-and-ten-year-old elf as emotionally mature as a fifteen-year-old human?" and "is it wrong to bang an eighty-year-old elf?").
  • Quite a few sources prior to 4th have suggested that elven infants mature fast enough that elves probably aren't in diapers for twenty years, The Order of the Stick nonwithstanding. It's not so much that elves take about a century to look like an adult so much as that elven culture doesn't really consider someone an "adult" until they've been living in elven society for about that long. Drizzt Do'Urden is a notable example, in that he was about 35 when he was exiled from his homeland and about 49 when he made his first appearance, yet appeared to be no younger than a teenager and no older than thirty throughout.
  • Fifth edition makes this explicit. Physically, they're mature at the same age as humans are, but Elven society doesn't consider them an adult until after their first century.
  • Averted for half-dragons (in some versions), who may not have left adolescence by the time others have died of old age. This is in line with dragon aging, where being 50 is the equivalent of the late teens and 100 is adulthood.
  • Kobolds have an odd version of this. They grow and age at about ten times the speed of dragons, meaning a kobold is basically fully-grown at five and physically and emotionally mature at ten. After that, though, they age incredibly slowly, with them not being weakened by age until their sixties and not dying of old age until they're double that or beyond (and dragonwrought kobolds can make it to their 200s). This is equivalent to dragons, which only stop growing at the age of 1200. However, few kobolds actually live this long, given their status as The Goomba; a "great wyrm" kobold is either incredibly dangerous or incredibly lucky.
  • In the Birthright setting, people can inherit divine bloodlines, which are generally assumed not to manifest until puberty. One such power is extreme long life, from five to one hundred times longer.
• Exalted:
  • Exalts (who may live anywhere from a few centuries to a few millenia, or even eternally depending on type) stop visibly aging until the very end of their extraordinarily long lifetimes. Since the average age of exaltation ranges from late teens to mid-thirties (there are exceptions of course. The youngest exalt was a preteen and still is after 1500ish years, while one of the oldest to exalt was over 60), they somewhat fit within this trope.
  • Also, the Terrestrial Exalted age more continuously and gradually over the centuries (or else their Exaltations would leave a good number of them as semi-eternal children), but do not move past their (physical) fifties or so until their lifespan draws close to an end. Since they always exalt before the age of 20, the rule for them seems to be normal aging until reaching full physical maturity (i.e. early 20s) before it slows down.
  • Solars, Lunars, and Sidereals who exalt as teenagers may follow a similar rule. The 1500-year-old preteen mentioned above has spent far too much time in the Wyld and is quite messed up. The others which aren't clearly adults in the artwork are all very young and inexperienced.
  • Strangely enforced for Infernal Exalted; part of the deal is having vitality restored, so the general body warping process of the chrysalis grotesque includes being brought back to a physical appearance that roughly resembles their twenties (ironically, the Infernals are, by default, the shortest lived Exalted, with a mere 150 year lifespan). Abyssals also get their vitality restored as part of their Exaltation, which generally involves rewinding to young adulthood or so; however, as one of the benefits of the "champion of death" thing, Abyssals don't age at all, and could theoretically live forever under the right circumstances.
• In GURPS, each level of Extended Lifespan doubles the amount of time spent maturing. However, Fast Maturation is available as a zero point ability with each level cutting time to mature by half causing the character to spend that much more time at their prime.
• In one of the earlier Shadowrun sourcebooks, a researcher notes that elves seemed to have some kind of mechanism that caused their aging process to stop for a period of time, but there also were indicators of a latent reactivation trigger that would kick in after a couple of centuries. He then went on wondering what if there were a few that didn't have that second trigger. There are a few. Harlequin is one of them. He's outlived pretty much everyone and every civilization.
• Played for Laughs (like just about every High Fantasy trope) in The Spoils. 3lv3s (elves) live for centuries, but spend almost all of that time as adolescents, rather than young adults, meaning that the Gearsmith Trade they call home is littered with juvenile pranks and toilet humor.
• Warhammer 40,000:
  • Juvenat treatments retard aging, but do not affect maturation—thus, nobles, Inquisitors, and other important people can appear to be in their thirties or forties at two to three hundred years of age. The treatments are not perfect, so the appearance of a very healthy 40/50-year-old is most common, barring additional surgery.
  • During the Horus Heresy the Primarchs and the Space Marines were both considered functionally immortal. The Primarchs rapidly reached maturity and then seemed to stop aging, while the process that creates the Space Marines is performed prior to puberty and bumps the subject into an eight-foot adult colossus. Post-Heresy it's a bit muddled: one Primarch is known to have survived for 1,000 years, but the rest are either dead, in suspended animation while inches from death, lost or Daemons (which immortality comes naturally for). As for the Space Marines, only one has been found to survive the 10,000 years from the Heresy to the setting's present, and he was rendered so infirm that he was unable to move and expired shortly after his discovery. The rest tend to last no longer than three centuries at war, with some reaching 1,000 years still able to fight — while there are mentions of the few Astartes who reach the millennial mark not being as spry as they were in their prime,^note Most notably, if Sigismund had been a century or two younger in the duel with Abaddon that kicked off the First Black Crusade, his attempt at a Mutual Kill would have succeeded, or possibly not have been necessary. the simple fact that they spend 95% of their lives travelling to or in combat zones means that the fortunes of war catch up with most of them well before old age becomes a problem.
• A character with high Essence in WitchCraft can see their aging slow to a crawl, to the point that one powerful NPC who looks to be in his mid-30's is actually over 1,300 years old. However, the game specifies that Essence doesn't slow growth, just the decay caused by age. It doesn't matter how high a character's Essence is as a child, they will age normally until they reach full maturity (i.e., mid-to-late twenties).

Video Games

• Disgaea:
  • This is pretty much how the aging process for demons native to Veldime works in Disgaea 2: Cursed Memories. Averted with non-Veldime demons, who typically have 500 years' worth of puberty to look forward to.
  • Angels also have the same problem as demons from netherworlds apart from Veldime. Flonne is the oldest from the trio of main characters of the first game at 1509 (Etna and Laharl are 1470 and 1313 respectively) yet all of them look like there's no real difference apart from height.
• In The Elder Scrolls, this appears to be the case for the Long-Lived racers of Mer (Elves).^note Though probably not the Orsimer. Of the few examples in the series' lore and backstory, Mer children seem to age similarly to human children until they reach adulthood, at which point their aging slows down considerably. Queen Barenziah, a Dunmer (Dark Elf), is the most prominent example. Her biographical book series portray her as growing up as a precocious teen and being considered an adult once she was 18 years old. That was nearly 500 years before the events of Morrowind where she's still alive and well, if noticeably aged.
• The Padjal of Final Fantasy XIV are a race of extremely long-lived, if not ageless, Horned Humanoids that cease visibly aging around adolescence. Some of the Padjal met in game have the appearance of a young child, while others resemble teenagers. The one who's most relevant to the story, of course, looks like a young adult. Padjal start out as regular Hyur children, but at some point during their childhood they are "chosen" by the Elementals of the forest. This causes them to grow horns on their head and stop aging. The Conjurer's Guild leader is one, and he comments that while he may look like a child to you, he is really a couple of hundred years old.
• Fire Emblem: The branded in the ninth and tenth games age according to their beorc heritage until they turn sixteen, at which point their aging processes slow down to match their laguz heritage.
• Fortune Summoners: Literally, for the Goblin-Elf hybrids known as the Elm, except they're not immortal:
  The typical Elm has a lifespan of roughly a millenia and a half; they age in a similar fashion to humans until the age of 20, at which point they appear 'immortal' like an elf.
• Hades: According to Eurydice, dead souls can choose which age they want to remain for the rest of eternity. Presumably, this is why Sisyphus looks middle-aged at most despite dying of old age in his myth, and why Theseus is still in his prime.
• This tweet from Masahiro Sakurai reveals how old some characters from Kid Icarus: Uprising physically are; Pit is 13 years old, Palutena is 22, Viridi is 8 and Phosphora is 16.
• Human-passing Nobodies from Kingdom Hearts can be inferred to have this. Word of God states they don't age, but the Nobodies who lost their hearts as kids seem to have aged normally since the time when they would have become Nobodies, while their fully-grown allies haven't aged a bit in the intervening decade-or-so (although Xaldin and Xigbar have noticeably different hair than Dilan and Braig, implying that continues to grow).
• In King's Quest II: Romancing the Stones (the fan remake of King's Quest II), Little Red Riding Hood is retconned into a girl named Possum who lives with her elderly sick grandmother. Her grandfather, in his youth, was turned into a vampire. Though he remained a friendly one, he went into seclusion, ashamed of what he had become. When he discovers that his elderly wife is about to die, he turns her into a vampire so she can live with him and be eternally young; as a result, she takes on the appearance of a 30/40-year-old. He also turns Possum, previously a squeaky-voiced child, into a deep-voiced fully grown adult.
• Averted by Zora in The Legend of Zelda: Breath of the Wild. The Zora race in the Era of the Wilds is long-lived compared to other Hyrulean races, but their growth process is appropriately elongated as well; a young-looking Zora girl notes that she's already an adult by Zora standards (and is older than most Hylian adults who visit Zora's Domain), but simply hasn't hit her growth spurt yet.
• The Mass Effect plays with this repeatedly:
  • Averted by the asari, who are generally thought to leave childhood at forty, and are considered mature (if rather young) adults at 80. A century-old asari is considered "barely more than a child". They give live birth and just how long gestation takes is never stated, but given a conversation in Mass Effect 3 between an asari and her shorter-lived non-asari husband involving their two children, it probably is less than a decade.
  • Played straight with the krogan, who are considered battle-ready at a fairly young age and stay that way for at least a thousand years. They're also explosive breeders, which is why the turians and salarians resorted to the genophage.
  • Miranda states that because she was heavily genetically modified, she will likely live 50% longer than a normal human, and it is stated that her body is in its twenties even though she is in her thirties. She makes no mention of whether this affected her growth rate as a child, though her genetically identical, but much younger, sister Oriana grew up having a normal life, which would presumably be impossible if all aging happened slower than normal, so presumably they play this trope straight.
• After her powers manifested, Aya Brea of Parasite Eve actually got physically younger. While she actively refused to use her abilities between games, by the time Parasite Eve 2 rolls around, Aya is permanently 21.
• The Sims:
  • In The Sims 3, supernatural Sims age normally until the Young Adult stage. After that, the lifespans of fairies and vampires are 5 times the length of regular Sims, and the lifespans of werewolves are 1.5 times as long.
  • In The Sims 4, Sims that are born vampires age normally until they become young adults. Once they reach young adulthood, they stop aging entirely.
• Ms. Fortune from Skullgirls has something like this. A stolen gem that she swallowed granted her immortality plus a wildly accelerated Healing Factor — which explains how she survived being chopped to pieces by Dahila and her goons who tracked her down to get the gem back. She hasn't aged a day since her supposed "death", and has worked out a way to use her newly-detachable limbs and head to her advantage in combat. Pity about the scars, though.
• Béluga and Elh from Solatorobo zig-zag this trope together. Béluga plays it straight, appearing to be a young adult despite his age, but Elh averts it by being stuck as a teenager. After losing her immortality, she comments that she seems to have finally grown a bit after three hundred years.
• Sonic the Hedgehog: As the Ultimate Life Form, Shadow the Hedgehog is completely immune to disease and his body will supposedly never age, and he's already over 50 years old. He's usually portrayed as physically the same age as the teenaged Sonic, if not a little older. The "supposedly" is due to the fact he's spent most of that 50+ years trapped in suspended animation, so it's something of an open question if he still has room to keep growing.
• Suikoden:
  • The True Runes keep their bearers from aging at all, leading to one character who's been physically a child for over three hundred years. The effects lasted long enough that they didn't even age while the Fog Ship Guide held onto the Soul Eater in Suikoden IV. Needless to say, Ted's a bit annoyed about this.
  • Apparently, after taking it off, some can live for much longer due to some lingering effects of the rune, and in some cases, like with the blue moon rune, gain immortality permanently as vampires, not having to feed as long as they're in range.
  • However, at least the runes allow bearers to hit puberty before the whole immortality thing sets in. Otherwise, characters like Luc and Sasarai who are implied to have had their runes since birth would still be infants. The theory is that the rune stops aging at its prime as defined by JRPG standard (i.e. mid to late teens).
• Raine and Genis in Tales of Symphonia. A bit jarring in Raine's case, as she looks the same age as her mother. As discovered later in the game, Kratos and Yuan both had their aging halted at twenty-something. Mithos, on the other hand, got it stopped when he was still a kid, and had to learn a special technique to make himself look older.
• Touhou Project, especially in fanon, plays with this trope for all it's worth, thanks to its huge cast of Really 700 Years Old characters. Most of the other characters, however, are adults who have lived thousands of years, and include some apparent teenagers who are truly immortal.
  • The Scarlet sisters were born vampires and have a literal case of Immortal Immaturity.
  • All of the fairies in the series are referred to in Perfect Memento as having at most the appearance of a 10-year-old child and Can't Grow Up. However, they may not fully fall under this trope, as they are elemental embodiments who are reborn each time they die (which may occur with the changing of seasons according to some interpretations) rather than being immortal or long-lived. The fact that the fairy maidens from the Scarlet Devil Mansion appear older than those anywhere else would suggest that fairies can age to an extent, but usually die before it occurs in any meaningful way.
  • Played with another way by Byakuren, who appears to be the standard immortal hot 20-something saint. Her backstory reveals she originally hit her 80s and looked every day of it before she achieved full magical control of her body. The first thing she did was restore her own youth; the second thing she did was give herself immortality.
  • Yukari, especially (thanks to dressing up and occasionally acting like a younger woman than she appears to be normally), gets jokes from fandom about being the "old maid" (in spite of only being a couple thousand years old, which is fairly normal by Touhou standards) by some corners, and having her boast that she's (eternally) seventeen by others.
• Night elves in the Warcraft franchise. As the novel World of Warcraft: Illidan puts it:
  He had the ageless look of a mature night elf, which meant he could be any age from twenty years to fifteen thousand.
• In Warframe, the aging process of the transhuman Orokin and their profit-crazed descendants, the Corpus, have been dramatically slowed down. Darvo is 105 years old, looks 20, and acts and is treated like an unruly teenager. However, the aging seems to stop at the mid 40s rather than 20s; Alad V, Frohd Bek, and Nef Anyo are all several hundred years old and look like 40-something fashion victims. Teshin was around when the Orokin Empire was at its height a millennium ago and likewise looks like he's in his early 40s. The Tenno look like teenagers or young adults, yet are nearly as old as Teshin. It's not made clear if it's from their life support systems, their times in cryosleep, standard Orokin augmentation, or their connection to the Void.

Webcomics

• Genetic elites in The Cyantian Chronicles, though their age catches up to them quickly as they reach the end of their lifespan (ranging from 120 years in foxes to nearly a millennium in wolves). But elite wolves don't reach their full height of about 7-8 feet for several decades, as Darius and his classmates are teenagers or mid-twenties but they tend to be pretty short (~6 feet) by their species' standards.
• In Dan and Mab's Furry Adventures, pretty much every long-lived creature race effectively stops aging in their 20s, as demonstrated by Cyra herself here. In the case of the Cubi, their major abilities do not awaken until their early 20s, and as one of those abilities is shape-shifting they can look any age they wish for the rest of their lives.
• Dragon Sanctuary has this for half-elves (but not for full-blooded ones, who must spend 100 years aging before looking the equivalent of a twenty-year-old human).
• Drowtales: Fae, such as elves and drow, age at half the human rate and stop aging at around sixty, thus making them the physical equivalent of a thirty-year-old human. A fae can wind up aging more than this due to a condition called mana deprivation if they go outside of the mana pool for too long, and if not treated quickly this condition can be terminal and eventually kill them, and even if it's corrected in time they can still look older than average.

• In El Goonish Shive, this holds true for elves, the children of Immortals and humans. Adrian Raven, the son of Pandora, has been stuck in his early twenties for multiple lifetimes. The same also applies to Immortals themselves; even when they "reset" (which they need to do every couple of centuries to minimize Sanity Slippage), their reset form will usually be physically and mentally a young adult. This even applies to Immortals who reset improperly, and thus do not inherit any memories from previous incarnations.
• Gunnerkrigg Court has Jones, who has existed since the Hadean eon (the formation of the Earth itself) and still appears to be a human woman in her late twenties or early thirties.
• In Hetalia: Axis Powers, it is shown that the Nation-tans age as children, but are usually stuck at 20 or so. Italy is shown as a chibi in the age of the Holy Roman Empire, but adult by World War I. It helps that a nation's age progression displays their development as countries.
• Homestuck gives us another long-lived example via Fridge Logic: higher-blooded trolls live much longer than lower-blooded ones with hundreds or even a thousand years' difference between their expected lifespans, but all of the trolls we've seen so far appear to have aged at the same rate.
• Toivo (and presumably Rosemary by extension) in Ingress Adventuring Company. Toivo claims he's "almost 70" but looks like he's in his mid-twenties. Contrast to his human ex Aidan, who's the same age and looks it.
• In Inverloch, elves seem to age at the same rate as humans do up until they are fully mature, and then they stop aging (except for the Severed, who are mortal and continue aging at the same rate as humans until they are cured).
• Irregular Webcomic!: Averted and lampshaded when one of the characters in the Fantasy theme (Mordekai) asks the elf Alvissa why her race hadn't outbred everyone and overpopulated the world. Her answer: "Elven children breast feed for 30 years, teethe for 20 years, throw tantrums for about 100 years, and don't take to toilet training until they're about 200... Elves invented effective contraception before we could use fire."

• Averted amongst elves in The Order of the Stick, according to Vaarsuvius:
  Haley: I can't really see the downside of—
  Vaarsuvius: Twenty years in diapers.
  Haley: Oh.
  • At one point, we meet a pair of elven children who are stated to be twenty-five years old. We're then told they're in kindergarten.
  • In a side story, an elven ghost mentions children breastfeeding for seventeen years. The humans she's talking to are horrified.
• Outsider: Downplayed. Loroi live for about 400 years; they reach physical adulthood at around eight years of age, and don't enter decrepitude until very shortly before they die. Consequently, their lives consist of several centuries of physical health and outward youthfulness — the only reliable way of telling old and young Loroi apart is that elders have longer noses and ear-tips — capped by a short maturation at one end and a short period of failing health at the other.
• In Pandect, Aces (animals with human souls and the ability to switch to a human body) stop aging entirely in their animal bodies, and the human body ages to about mid-20s and then remains there for the rest of their (very long) lives. Justified in that they have to earn Ace: the prolonged period of youth is part of the reward.
• In Tower of God, Rankers are people who have both climbed the tower high enough and mastered Shinsu to the point that they are completely immortal. Almost all of them look extremely young, when in fact each and every one of them is at least five hundred years old, that being the average time it takes to become a Ranker in the first place. For example, Anaak Jahad is an extremely short and childlike lizard person who is in fact three hundred years old.

Web Originals

• Humanity in 17776. The entire human race mysteriously stops aging or dying (or reproducing) in April of 2026, but it's then clarified that children conceived before that date are still born and grow to adulthood, as do those who were still children at the time.

Western Animation

• Castlevania (2017) has the Dhampyr Alucard, who aged very quickly through his childhood and who will now presumably keep his young-adult looks for many years to come.
• Most of the alicorns in My Little Pony: Friendship Is Magic. Justified with Twilight Sparkle, as she is seen to become one while she is young.

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