Breast Expansion

Conveniently, the laser also made her bra bigger.

"What on Earth have you done?! My maguppies became bazongas!"

— Marge Simpson, The Simpsons, "Large Marge"

A character suddenly finds their breasts enlarged to often immense levels, via Applied Phlebotinum, magic, science, or otherwise. Mostly happens to flat-chested characters suffering from A-Cup Angst, though women on the other side of the spectrum may have it happen as well. Due to the Buxom Beauty Standard, this is often played for Fanservice. Sometimes the actual growth tends to be as important as the final size of the breasts. It is also frequently played for comedy. An Overnight Age-Up for women usually guarantees this will happen.

If the expansion is merely caused by puberty, there's a separate trope for that. If the expansion is done on a meta-level, see Adaptational Curves. An alternative is Fake Boobs. For the whole body expanding see Inflating Body Gag. On rare occasions, its logical conclusion is "Pop!" Goes the Human.

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Examples

Advertising

• One banned Japanese commercial shows a woman drinking milk and her breasts growing. What Were They Selling Again?
• A commercial for Brahma features two girls who have their breasts grow as a result of a nearby man blowing up a beach toy.
• An advertisement for the racing game Juiced features two teenage boys finding they can enlarge the breasts of a nearby girl and strip her of her clothing by modifying their in-game car.
• A green tea commercial from Thailand has a woman enlargening her breasts by grabbing her belly and shoving her stomach fat into her chest. The woman standing next to her attempts to do the same thing afterwards, but fails.

Anime & Manga

• The 100 Girlfriends Who Really, Really, Really, Really, Really Love You:
  • In Chapter 77, both Hakari and Karane get into a bath that enhances their chest size. Karane refuses to leave it, knowing that her chest size will return to normal once she does, but Hakari manages to talk her into doing so.
  • In Episode 7, Hakari fantasizes that Kusuri's drug will give her extra-large breasts and buttocks, with significant attention given to how much they wobble.
• Abunai Sisters: One of the sisters' powers is to make their chest grow in size. In one episode, they use this to help cushion them in a car crash (making it a literal case of Funbag Airbag), and in another, they use it to break the ropes used to tie them up.
• Chapter three of the manga series Asklepios has the protagonists trying to convince a village girl to let them operate to remove a tumor on her ovaries that's caused a huge increase of her bust size, but at the same time is killing her. She initially refuses because she thinks her love interest likes big breasts, but eventually accepts the surgery when he says he cares about her and not her bust. After the surgery is over, he even says she looks better flat-chested.
• In an early chapter of the quite obscure manga Benten-sama ni wa Iwanaide (loosely, Don't say that to Benten), this trope is magically invoked by a selfish and petty guy who uses the goddess Benten's power as part of a convoluted plan to publicly humiliate a woman who rejected him. The target's bust begins to slowly and steadily grow (as a convenient digital readout conveniently tracks her gradual progress from 80 to 124 centimeters), and in the meantime she rashly agrees to fill in at the last minute for the role of a princess in a children's play, which naturally involves wearing a very tight-fitting costume. Between the enchantment's progress and her fellow actors' energetic antics, the result is as predictable as it is spectacular.
• In Black Butler, episode 23, a slightly-endowed Angela tries to tempt Sebastian by showing off her assets, and they actually look bigger than in previous episodes. Possibly justified by the fact that she's not human anyway.
• In A Certain Scientific Railgun, there is an Urban Legend for something called the Bust Upper, that is either a technique or device that can increase breast size. During the Dream Ranker Arc, Mikoto Misaka and Saiai Kinuhata investigate the existance of an Indian Poker Card said to contain information of the Bust Upper. They managed to get hands on a bunch of cards that include one with the Bust Upper info, but because they have to the check the contents of the cards manually and one card at the time, they unknowingly miss out when a crow makes off with the card and drops its in the hands of a Bit Character, who uses the contents of the card to enlarge her own breasts.
• In Change 123, when the main character's split personalities manifest, her appearance changes due to subtle differences in the placement and internal balance of her muscles necessary for their different combat specialties (attack power, speed, and defense). The usual sign that the childish grappling specialist has come out is that her boobs instantly "grow" big enough to snap her bra (or bikini top on occasion). Presumably this is the result of her pectoral muscles pushing them farther out than usual.
• In one Crayon Shin-chan episode, Misae imagines herself with hugely enlarged breasts.
• In Cyber Team in Akihabara, Kamome one of the five Magical Girls is ashamed of being flat. So she uses a pump to inflate her chest in the beach episode, and handily attracts a gaggle of boys. Also, all of the girls get pretty damn big when they transform.
• In the newer Dirty Pair series, Dirty Pair Flash, Kei's transformation scene sometimes includes her breasts doubling in size and ripping through her shirt.
• Just like her muscles, Caulifla's boobs grow up a lot when she transformed in a Super Saiyan Third Grade in Dragonball Super.
• In Fairy Tail, Brandish has the ability to alter the size of almost everything. She uses it on Lucy's breasts for fun. At first Brandish shrinks her breasts, but then swells them up to becoming the biggest bust in the entire series (Which is really saying something) giving Lucy some very understandable D-Cup Distress. Fortunately for Lucy, Brandish only does this for about a second.
• Chapter 4 in the manga Franken Fran featured the titular character (an insane Body Horror plastic surgeon-cum-Frankenstein's Monster) passing out free cosmetic surgery to some kids at a school that yields almost instant results with no recovery period. Besides odd instances like a couple who wanted to be stitched together, or having a love message drilled into your teeth, one girl apparently asked for breast implants twice as big as her torso! The terms "overcompensation" and "something to prove" comes to mind. Hilariously enough, she calls out the other students for the procedures they had done on them, saying that they "lack restraint" and the kicker being that compared to most of the students she's right.
• The Gag Dub of Ghost Stories subverts this trope. Satsuki tries to get a wish granting ghost to give her "huge boobs", but does it wrong so it doesn't happen.
• In Gou-dere Bishoujo Nagihara Sora, the flat-chested girl Tenka Morooka gets this unwillingly at the end of chapter 3. At first she doesn't want "them" because they are "heavy", but in the end she decides to keep them.
• Grenadier had one episode where the enormously well-endowed main character's flat-chested cohort, Mikan, puts on a pair of big inflatable breasts, ostensibly to show off for her friend it appears.
• Subversion: Once, Makoto of Hell Teacher Nube stole a bag of magical dust from a benevolent youkai — dust with the power to make anything grow. Among the many scenes of carnage (such as extending Nube's prodigious eyebrows down to his knees, or causing Noriko's cute crown of flowers to completely engulf her,) Miki sprinkled this dust on Kyoko's chest. It inflated... inflated... INFLATED... and just when Miki was horrified and outraged at being surpassed, and the entire classroom stared, two actual melons dropped out of Kyoko's blouse, as the dust had only affected a couple of seeds that had dropped in there during lunch.
• Despite its focus on breasts for fanservice, High School D×D shows surprising restrain with this trope (admittedly because most of the girls are plenty stacked already). In fact, the one time it's used, it's inverted. Turns out Issei can borrow power from Rias, but the process makes her boobs shrink. Issei is horrified, but they grow back when she sleeps.
  • This is later played straight in a realistic manner concerning Asia, who in the year she has been a devil, has grown to equal Xenovia and Irina in the bust department. According to Ravel, this is due to a combination of demon physiology, demonic power, and her own desires to have Issei see her attractive. (It's hinted Ravel might just be overthinking it, Asia's at a the right age and the series covers enough time for a perfectly normal frontward growth spurt.)
• Jungle de Ikou!'s entire plot centers on a flat chested girl with breast-obsessed friends, who becomes the tall, tanned, massively buxom woman she always wanted to be thanks to magic. Unfortunately it also unleashes a demon bent on destroying mankind... fortunately he's more than happy to just stare at her boobs.
• Episode nine of Kamen no Maid Guy features an entire restaurant which hires only busty girls so the waitresses can use their assets to distract the predominantly male customer base from noticing the horrible food. Nekka, the main heroine, is sent in to "investigate" by her flat-chested friends because they feel their restaurant is being "outgunned". It turns out that all the waitresses have had boob jobs, while the manager is a flat chested girl who's been padding (to a ridiculous extent) the whole time.
• In Last Period episode 9, Android Sonya's breasts increase in size over the course of the episode. When she is defeated at the end, they explode, a reference to the Samsung Galaxy phone's problem with exploding batteries.
• Magical Canan's protagonist Chihaya has a mild issue on her small bust. When she transforms into her alter ego, Magical Girl Carmine, the camera intently zooms on how she grows her breasts and butt's sizes. They shrink back when she turns to normal.
• Magical Girl Lyrical Nanoha ViVid. Seinen series with a Older Alter Ego Transformation Sequence. Naturally, one of the panels focuses on the character's breasts that had grown to large proportions.
• The second episode of Magical Shopping Arcade Abenobashi had Sasshi defeat the final boss by using a magic talisman that Arumi bought, which turned out to be used for breast expansion - the boss's chest swelled up so much it exploded. Yikes.
  • It should be noted that this was a giant monstrous skeleton in armor.
• Magical Warfare: In the first episode of the anime, Isoshima's breasts grow due to magic powers.
• Mahoromatic: Mahoro is fairly insecure about her relatively small bust. She's, therefore, understandably upset in the dream sequence episode where her breast enhancement device works on Minawa, Shikijo, and even the male Suguru, but not on her.
• In the manga Manyu Hikencho, the story is set in a fictional fantasy world where Buxom Beauty Standard is enforced as breast size determines a woman's worth and position in society]]: small-breasted women are outcasts and well-endowed women are showered with wealth and power. The main character, a ninja named Chifusa, is a "thief" who steals breast size from busty girls to add to her own and gives advice to flat-chested girls on how to increase their bust size, in someways being a "robin hood" of breasts. Interestingly, Chifusa herself hates having large breasts due to them often giving her unwanted attention, so she views her ever-growing bust as more a curse than a blessing. Eventually there is an entire episode dedicated to Inverting this trope when Chifusa's breasts get so incredibly huge she can barely stand let alone fight, though even after she succeeds in shrinking her breasts she still ends up by with far the biggest bust in the show by the end.
• Yuki the Ice Spirit from Master Of Mosquiton gets a transformation sequence where her breasts literally inflate like balloons when she turns from a Token Mini-Moe into a buxom hottie.
• A rare non-human example happened in Mazinger Z. In episode 32, Kouji and Sayaka have to battle a flying Mechanical Beast (Gelbros J3). Kouji thought replacing Aphrodite A's Torpedo Tits for bigger missiles would help to defeat it. It Makes Sense in Context.
• Discussed in Miss Kobayashi's Dragon Maid. According to Tohru, Ilulu's chest is a result of her poor transformation skills, and they would get even bigger were she to relax what little control she had.
• In Monster Musume Female minotaurs, whom already have huge breasts, can have their breasts become painfully swollen and even larger if they're not milked regularly. We see the aftermath of this with Cathyl whose breasts have become massive since her boyfriend hasn't been available to milk her.
• My Dress-Up Darling: Marin isn't exactly lacking on the chest department, but when she does her first cosplay she notes that the character has bigger breasts, so she wears two nubras to expand them to look much closer to her. This latter causes her to get uncomfortable since Gojo made the dress for her exact size, and he's forced to adjust it lest she suffers a Wardrobe Malfunction.
• A breast inflation spell has been used twice in Negima! Magister Negi Magi. The results are always a hilarious fail:
  • In one example, Asuna gets in an argument with some other girls over breast size. To help her along, Negi enhances Asuna's breasts by using a spell to make her swim-suit inflate like a balloon. At first Asuna happily belittles a snooty blonde girl who was making fun of her, but then the spell backfires and she overinflates, causing the chest area of her suit to explode.
  • In the other Anya and Nodoka attempt to inflate their breasts through sorcery, ends with them humiliating themselves in front of their classmates by overinflating and floating away like balloons.
  • However, Makie manages to mildly inflate her chest and drain Yuuna's... in a dream sequence.
  • A Drama CD involving Yue and her Ariadne friends has them point out how flat-chested Yue is and they offer to help her by using this spell. Of course it fails.
  • At the end of the story, Nodoka's breasts have started to grow as a result of being in low gravity.
• In the manga Okitsune sama de Chu a cow demon possesses a girl and causes her breasts to grow from flat to about the size of her head. They eventually grow to almost fill a room. Even when the demon is removed, she keeps some of the expansion. It happens a few more times throughout the series.
• In the Transformation-tastic episode of Onegai My Melody, a skinny underdeveloped girl uses (kinda') dark magic to steal other girls' physical features. Aside from stealing one girl's face, and a leggy Tomboy's legs, she also steals a busty blonde's chest size, and some hips. By the time she's done, no one who knew her before even recognized her. Her plan falls apart when she gets greedy, causing the spell to go haywire when she tries to take on too many enhancements at once. This is episode 24 season 1, in case you are "interested".
• In Pokémon: The Original Series's episode "Beauty and the Beach", James of Team Rocket wears a breast-expanding bikini top and taunts Misty about his greater size. When the episode was finally aired in the West, the scenes featuring this were cut.
  • Inverted with May - her breasts (possibly due to being Off-Model) go from the size of a grown woman's in Pokémon the Series: Ruby and Sapphire to mosquito bites by Pokémon the Series: Diamond and Pearl.
• In Puni Puni Poemy:
  • One episode sees some of the characters (including the Token Mini-Moe) imagine what they would do with the titular character's magic powers...two of them, including the Token Mini-Moe, imagine them making their breasts larger.
  • Meanwhile the girl with D-Cup Distress pulls the inverse, imagining a world where she's finally flat and free of back pain.
• In Queen's Blade, the character Melona (ironic name) can fire corrosive liquid from her breasts as an attack. When Leina fights her a second time, she has a countermeasure: a special suit of armor that is coated with wax, making it immune to Melona's acid. Knowing she's outmatched, Leina tricks Melona into attempting an acid attack before dashing up and grabbing Melona in a bear hug. The acid backs up, and inflates Melona's breasts to the point they explode, killing her. Of course, lucky for her fans, it was just the first episode and she's quickly revived by the Big Bad. Melona is a demonic blob creature in human shape whose body consists of highly acidic jelly, so there is some explanation for how she does this (as well as survive).
• In The Qwaser of Stigmata, Oribe Mafuyu's breasts grow from one of the smaller girls in the series, to the biggest, thanks to the use of her sword which draws energy from breast milk. In the manga this also happens, but over time rather than all at once like in the anime.
• In Rosario + Vampire, removing Moka's rosary causes her true vampiric self to emerge. In addition to a massive increase in power and a change to her hair and eye color, the transformation causes Moka's (already fairly noticeable,) breasts and buttocks to enlarge even further.
  • Yukari has an imagination spot where she pictures herself with breasts bigger than Kurumu, before they grow so big the imagination spot pops. This was in the same episode she had aged into a teenager where the only one bigger than her was the resident succubus.
• Sailor Moon Super S Episode 17 featured an odd variation of this. One of the monsters of the week shows up as a flat-chested girl in a swimsuit. She then produces two magical balls and swallows them, and instantly grows boobs of the same size. The action then freezes and a message comes up reading "PLEASE DO NOT TRY THIS AT HOME."
• School Days: Episode 5. One of the girls uses an inflatable bikini inserts to give herself large breasts. That's also in the original game, and the girl who did that was the local flat chested girl Setsuna.
• A subversion occurs in Slayers when flat chested Lina Inverse was told of a fountain that makes things grow as a reward for a quest. It turns out the magic spring she was told of would have made her old.
• Strike Witches: Episode 7 of Strike Witches: Road to Berlin has Lucchini discover the power of a hidden idol that causes her boobs to grow to much bigger sizes. She then spends the episode spreading it to the rest of the cast by groping them.
• In To Love Ru, one chapter has Golden Darkness use her shapeshifting powers for this purpose. When Rito see her, she is very embarassed.
  • In a chapter of the sequel To Love-Ru Darkness, Lala invents a machine that does this. Though all it really did was transfer the size of one's breasts to another for a brief period of time.
  • Nemesis' breasts are seen expanding several times. She's an amorphous cloud of dark matter that alters her physical body to whatever best helps her mess with people.
• An episode of Tokyo Mew Mew involved the girls fighting a pair of birds who inflated their breasts to use as weapons. Specifically they use them as balloons, bounce the main heroine around till she's dizzy, and chasing the boys around.
• UFO Ultramaiden Valkyrie:
  • A scene in episode 1 of season 2 after Valkyrie makes a cookie bigger with a time key. Just after that Hydra makes a joke about making Akina's breasts bigger. Guess what happens.
  • The series as a whole features Breast Expansion heavily. Every transformation sequence features prominently a scene of Valkyrie or Hydra inflating their breasts as they turn into their adult forms.
• In UQ Holder!, Dana is able to make Yukihime's breasts and butt grow, giving her the appearance of a fertility goddess. It's a sign of how powerful she is, since she was able to ignore Yukihime's incredibly strong barriers.
• When three of the angels in Wedding Peach switch bodies with magical cats, the girls turn into Cat Girls, and their breasts grow. Their breasts shrink back after the girls return to normal.
• Yuuna And The Haunted Hotsprings:
  • In chapter 150, due to some food sent by the landlady from her trips: Miria, Matora, Yaya, Chitose, Koyozu and Nonko had their breasts expand to ridiculous levels.

Audio Plays

• The Firesign Theatre had a fake advertisement for "Boobie Chew", a gum that would make your breasts larger, on one of their albums. "Boobie Chew will grow on you!"

Comic Books

• The comic 3 Little Kittens, by Jim Balent, features the villainous Latex Red who takes breast augmentation to a new extreme...her implants are filled with explosives, so if you kill her you blow up too.
• While originally portrayed as flat-chested, The Authority team member Shen Li-Min, aka "Swift", eventually paid for some very expensive breast implants and likes to boast about it. Given the nature of the series this is probably making fun of other well-endowed comic heroines.
• In the parody comic Babewatch, all the female characters have unusually large breasts but one of the characters has inflatable breast implants she can use as a life preserver.
• Another comic known as C.H.I.X, a parody of many of the tropes associated with heroines. Its main character 'Good Girl' is a Flying Brick who stores energy in, and whose powers and intellect are proportional to the size of her breasts (the bigger they are the dumber she is). She starts out the comic giving a heartfelt speech, but only a few panels in her breasts grow back from flat to huge and she forgets what she was talking about.
• In Gen¹³, one of the side-effects of Caitlin's gen factor activating for the first time includes her cleavage expanding into CLEAVAGE.
• The aftermath of the Conquest event in Invincible, Eve reforms her body from scratch; after awakening in an intense care unit Mark is happy to see that she's alive and fine, then he notes that her boobs look bigger, Eve remarks that when she rebuilt herself some "improvements" were unconsciously made. That said, her bosom doesn't look any different than usual, Eve was always quite busty since day one, the way Mark immediately notes how bigger she is now doesn't match the unnoticeable "change" in her actual design.
  • Later it turned out that Eve was pregnant, which may have had something to do with it.
• Little Ego had a story in which Ego found a cream that caused her breasts to grow. Although initially delighted, they continued to expand till they were too big for her to exit the room. Being a Little Ego story, it was All Just a Dream.
• Outgunning even Power Girl effortlessly by a factor of HUGE is the short-running (and deliberately-comical) superheroine Mammary Woman, who appeared in the now-defunct British humor comic UT. Initially a parody of Spider-Man, the heroine was a put-upon nerdy schoolgirl with a very flat chest whose life changed forever when, on a visit to an underwear factory, she was bitten by a radioactive bra-strap. Later that night, the inevitable sequence occurs, as in the space of three frames her assets swell from bee-stings, to basketball-sized (bursting her school blouse open in the process), to about the size of three metres across and a triple-Z cup...EACH. She decides to use her superhuman boobs for the power of good, and so becomes the World's bustiest superheroine, Mammary Woman. In one later episode, she even expands them even further in a matter of seconds to about the size of a military hovercraft each, in order to buffer a crashing train and save its crew and passengers...
• Mimi Masters in Fred Perry's Ninja High School story "Minor Adjustments", waking up to find that (with a little help from her equally sorcerous sister) she's magically sprouted medicine-ball-sized sweater-stretchers on her previously flat chest overnight.
• In Jules Feiffer's Passionella, when Ella the chimney sweep transforms into Passionella the "beautiful glamorous movie star," one change that sticks out is that, while the former shows no perceptible bosom in her shapeless shift, the latter's breasts extend twice as far as her nose.
• Miss Adventure, from Penthouse Comix, transforms from flat-chested to incredibly buxom when she transforms into a superheroine.
• Casey from Strangers in Paradise gets breast implants. Twice.
• Much like the TV series that it spun off (see Western Animation below) the W.I.T.C.H. comic features this. Since the characters are mainly teenaged girls breast size features heavily in their major concerns. Will, the team leader, is a flat chested girl who uses her enhanced Magical Girl form to offset her lack of size, while tomgirl Irma is already the biggest, but tries to make herself bigger anyway out of pure vanity.
• One of the first foes faced by Young Justice was the Mighty Endowed, an archaeologist named Nina Dowd ("N. Dowd") who was transformed into a top-heavy feline figure too well endowed to support her own weight. In a twist, despite her being fully clothed, her new assets are never clearly seen.
• Oddly enough though many comic book females are possessed of the Most Common Superpower, several are also acknowledged to have had their breasts surgically augmented. Among them Outlaw (from Deadpool), Emma Frost (from X-Men), and Cat Grant (from Superman). Jessica Drew is a maybe...depending on how you interpret this◊
  • The writer for that comic in which that panel took place outright said it when comparing Spider-Woman with Wonder Woman "Spider-Woman has better hair, better costume, Frank Cho implants and a fucked up origin"
  • As it happened, that turned out to be the exact scene where Drew was replaced by Skrull Queen Veranke.
• Played for horror in the Black Alice issue for the Helmet of Fate miniseries. One of the many annoyances in Lori's life is Mrs. Hartmann, a neighbor who tries to maintain her appearance with cosmetic surgery and keeps telling Lori she should dress in a more feminine manner. When Lori discovers the Helmet of Fate and tries to make it serve her, the helmet punishes her by lashing out at everyone she resents. One of the victims is Mrs. Hartmann, who is subjected to this trope — and judging by her reaction, it's very painful.

Fan Works

• Candy in the Gravity Falls older AU fic The Big Pines uses the size changing crystal flashlight to give herself larger breasts in order to catch Dipper's attention. She shrinks them back down to normal later after realizing she didn't need them in the first place....and later admitting that just suddenly making her breasts grow from quite small to G-cups in an instant without strengthening her back muscles gave her terrible back pain.
  • Mabel in this story also qualifies. Her breasts may have grown naturally, but they grew so much in such a short amount of time ^note  Mabel reluctantly admits she's a Q-cup bordering an R-cup, and was a late bloomer as she barely seemed to grow for much of her time in High School, who only started seriously developing near the end of it that everybody in school thought she got giant implants.
  • When Mabel, Pacifica and Candy are all hooked up to a machine that induces nightmares, all nightmares involve or have some element of breast expansion.
    • Mabel has a nightmare were everybody treats her like shes nothing but a pair of breasts with legs, which causes her breasts to start expanding until their the size of a building and eventually absorbing her. Leaving her as literally nothing but her breasts.
    • Pacifica has a nightmare where she's back under the yolk of her parents, who forced her to have so much badly done plastic surgery that she looks more like a Cenobyte than a human being. Most prominent is a pair of enormous implants that are larger than Mabel's bust but are obviously cheap and look terrible.
    • Candy's nightmare has her going around stealing her friend's best traits, based on her feelings of inadequacy compared to her friends. Including Pacifica's behind. Grenda's strength. Wendy's face and Mabel's bust.
• B--B NOTE by D'arkYagam'i ^note yes, that one) is all about this. A new Kira shows up who, instead of killing criminals, uses a Boob Note to give them gigantic breasts. Everyone, man or woman, begins breaking laws just to get bigger "roundajigs". At the end, the Earth becomes a boob.
• Child of the Storm has Diana a temporary case of this when, along with Harry and several of their friends, she gets hit by a Plot-Relevant Age-Up from a Genius Loci to make them old enough, and thus, powerful enough (though as is demonstrated, power does not necessarily come with the skill to use it properly) to protect Bobby Drake. Since she's about 12 at the time, and is the pre-teen version of the famously well-endowed Wonder Woman, this is inevitable. Unlike most examples, she's not especially happy about it, finding it notably uncomfortable and disconcerting, and isn't bothered when it wears off.
• Glorious Shotgun Princess: Shepard notes that a side effect of becoming a Solar Exalt is that her breasts grow slightly (but noticeably) bigger. It seems to be just part and parcel of "accentuate everything that makes her interesting and unique;" she notes that a few of her scars have disappeared, but some of her more attractive ones have gained definition, and her freckles are more visible too.
• In the Naruto and Kenichi: The Mightiest Disciple crossover Naruto Rebirth of the Rikudo Sennin, Thanks to Naruto's strict diet and training regime Kisara goes from calling Miu a milk cow to worrying that using the name would be hypocritical since she's now the bustier of the two.
• Several women in One Punch Man: Hero's Harem grow noticeably larger breasts and butts after eating Kombu Infinity's seaweed. Mizuki and Beast Queen don't notice due to eating small amounts regularly over a considerable time but Do-S, who was force-fed a considerable amount, complains about having grown two cup sizes.
  • Vaccine Woman and Deep Sea Queen (Deep Sea King's sister) both grow larger breasts in their super modes with the former permanently becoming bustier as she absorbs pollution.
• In Thousand Shinji, when Rei transformed into Reigle, she used her control upon her body mass to expand her breasts.
• Chris McLean in Total Lady Drama Island accidentally gets sent a barrel of weird goo while ordering provisions for the contestants. The goo turns out to be an experimental meal substitute that, as Chef puts it, "has more calories per teaspoon than a stick of butter" that was meant to be used by soldiers to replace rations. Chef decides to feed it to the campers, causing growth in... certain areas. All of the girls' bustlines grow rapidly as the food digests, to the point that that Heather has a bust as big as Lindsay's had been and is still the smallest, while Courtney is described as having breasts larger than basketballs. Cody, the only boy who had eaten it, gets a different sort of growth .
  • Exaggerated with Anna Maria, who steals and eats the rest of the goo herself because she's upset that she's the second smallest girl on the island after the initial growth (at a "mere" H-cup). She consumes so much of the experimental chemical that each breast ends up weighing more than her, and she can barely stand (let alone walk) without help.
• In a nameless Touhou Project fancomic, Sanae tries a full power item for the first time and it gives her H-cup breasts. However, it turns out this was because she didn't know how to use it correctly, as Reimu and Marisa turn hugely muscular when using one instead.
• Two examples in Webwork: Jade notices that her new spider demon body has larger breasts than her previously met future self. Later on her old teacher finds that her breasts are bigger after her own transformation into a bat demon.
• In Level Up (MHA) Gamer Izuku can add stat points to himself and his party, increasing charisma increases Breast Size on female members. Some of Izuku's Power-Up food has charisma +1 as it's main effect.
  • The water in the Peaks of Plenty dungeon increases a woman's charisma and strength. Nejire stays in the water long enough to have island sized breasts.
• The protagonist of the Worm fanfic Pick Your Poison is a tinker with a specialty in bacteria, who creates a super powerful health supplement that causes a form of 'super puberty' which makes everyone who takes it taller stronger, while causing women who take it to develop larger, lactating breasts which keep growing as long as they take it, especially if they 'stimulate' their breasts while still taking it. When Taylor starts taking it, she grows into a double D almost overnight, and could still be considered flat compared to other women taking it, who even with super strength, the protagonist wonders how they can stand up without being hunched over.
• Nabiki Tendo's breasts grow about two or three cupsizes after she eats her Devil Fruit in Voyages of the Wild Sea Horse.

Films — Live-Action

• In American Pie Presents The Book of Love, an imaginative nerd fantasizes a pretty girl taking off her top where her chest quadruples in size with some movie magic. Hilariously, they grow so massive that they literally pop to burst his bubble and snap him back in reality.
• In Are You Being Served?, Grace Brothers have an expanding bra, the Lifebelle Inflatable Swimsuit, on sale (in case the wearer comes across a rock star), which comes in handy when Mr. Humphries (disguised as Mrs. Slocombe) is attacked by randy revolutionary Cesar Rodriguez, only to be startled by the sight of the "breasts" expanding rapidly, which allows Mr. Humphries to make a quick getaway.
• Believe it or not, the climax of the '60s British comedy film The Bliss of Mrs. Blossom hangs on a character sabotaging a demonstration of a new kind of inflatable bra causing the bras to inflate out of control.
• In the comedy horror B-Movie Bolt Neck, one character is a tremendously insecure teen girl. She disappears after the monster, a Frankenstein ripoff, shows up and everyone thinks she was killed...turns out she left to get illegal breast implants overseas. At the end she displays her newly inflated chest to the whole school, with just the results she hoped for.
• Bruce Almighty: Almost immediately after receiving God-like powers from God himself, Bruce attempts to make his girlfriend’s breasts bigger.
• In the horror film Corpses the evil force causing the ruckus in the film causes one of the female character's boobs to swell up till she explodes.
• Dude, Where's My Car?:
  • In the end, when Jesse and Chester's girlfriends put on a pair of mysterious alien necklaces, they each gain a couple cup sizes. Jesse and Chester meant them as gifts for the girls, but the necklaces were left by the aliens as gifts for Jesse and Chester.
  • When the Jumpsuit Chicks are fusing together and transforming into the Super Hot Giant Alien, the Alien giantess' breasts grow a couple breast sizes, complete with a cartoony ballooning sound.
• Parodied in Epic Movie (2007). The Mystique-expy played by Carmen Electra seduces one of the main characters, who asks her to increase her breast size. She obliges, then does the same thing with her hips. Then the requests get increasingly bizarre, like asking her to grow a unibrow and make herself older and fatter.
• Everything You Wanted To Know About Sex ^note But Were Afraid To Ask. John Carradine plays a Mad Scientist of the Masters & Johnson's variety. One of his subjects is being fed silicone into her chest 24 hours a day. "She used to be flat chested, now look at her!" When the lab explodes, a 50 foot breast starts terrorizing the countryside.
• Faust: Love of the Damned: There's a scene that goes from breast expansion right into Body Horror without any warning when "M" punishes his mistress Claire by briefly melting her.
• The historical comedy Gladiatress. One of the three sisters returns to her home with boobs that have grown via magic and is now able to order about her French husband, who previously rejected her for being a Pettanko.
• In Jane Austen's Mafia!! Vincenzo makes a wish under a falling star in one of the flashback scenes. His new girl friend's breasts expand (apparently without her noticing).
• In Jekyll And Hyde Together Again, Tim Thomerson plays a plastic surgeon who gets distracted while helping a patient get larger breasts and winds up pumping her up to a cartoonishly large size. When he offers to fix her, she refuses, saying her husband is going to love them.
• Killer Klowns from Outer Space: Near the end of the film are two female Klowns whose breasts blow up just like balloons.
• A similar situation occurs in the movie Leprechaun 3, where a woman wishes for a new, busty body on one of the titular imp's gold coins. She gets it, but then the Leprechaun shows up and causes her breasts (and hips) grow out of control until they pop.
• The short Mood Boobs is basically twenty minutes of just this, when the main character Amanda accidentally uses a magic stone to make her boobs change in size and sensitivity depending on mood.
• In My Super Ex-Girlfriend, the flashback scene where Jenny gets her powers makes it unmistakably clear that they include the Most Common Superpower.
• In Howard Stern's Private Parts, Howard is at an airport and sees a hot woman walking by; he imagines her in only a bra, and then imagines her breasts getting larger.
• Repossessed: The gym scene has a girl using exercise machine. With every rep her breasts blow up just like a balloon. Later a pop is heard off camera.
• In Terminator 3: Rise of the Machines, the T-X increases her breast size at one point to distract a cop who pulled her over.
• In the comedy Twinkle Twinkle Lucky Star, a man becomes able to grant wishes, hence the name. One instance includes a woman who wishes for enormous breasts, but he decides to make her breasts so huge she becomes unable to stand, a la the Mighty Endowed.
• In When Evil Calls, Alice's boyfriend wishes that her breasts were bigger. Her breasts grow until they explode.

Literature

• A girl in The Clique series has a similar problem: Alicia develops way more rapidly than anyone expected...allegedly naturally, but it's implied otherwise (keep in mind this is a 12 year old girl). She's surprised and embarrassed when she gets teased for her overinflated look by the other girls. Guys however are way more impressed.
  • It's also implied her parents forced her to get them. It's a pretty messed up book series.
• In Dork Diaries, the central heroine punctuates her stories with drawings to explain the narrative. One of which is her fantasy of what she wishes she looked like...complete with larger breasts and an arrow pointing them out specifically, along with other cosmetic enhancements (though, unlike many characters here, they were simply very large instead of comically huge).
• In Fatal Beauty by horror novelist William Schoell, a corporate executive who's unhappy with her bust size uses her company's new miracle cosmetic product to increase their size. Unfortunately, the product is made from the secretions of psychic genetically engineered monsters, so it causes horrible problems to all the test subjects. In her case, the tits grow enormously large and develop a mind of their own, turning homicidal and prehensile, and her best friend is forced to kill her to save herself and others.
• The title character of Lucy Taylor's short story "The Flesh Artist" is Cyrus Sweet, a sociopathic plastic surgeon who convinces his lovers to let him "improve" them. Evelyn, the small-busted sculptor who grudgingly agrees to go under his knife, receives a gargantuan pair of mongers. She dumps him immediately. Sadly, her problems have just begun. Years pass, and Sweet pines for "Tits" (his charming nickname for Evelyn). He looks her up, gets an invite to her house, and makes several awful discoveries, all related to the leaky sillicone he planted in her chest... and the terrible yet apt revenge she takes on him for doing it.
  • This is actually similar to an online Breast Expansion short story, about a millionaire who becomes obsessed with a porn star's breast implants and coaxes another girl into getting dangerously oversized implants herself. Oh and the porn star, named "Mountain Tops", is mentioned in the epilogue in a passing, saying her breast implants "exploded" not long after...
• In the Gossip Girl prequel, It Had To Be You, one of the girls becomes insecure that her breasts aren't growing, tries to enlarge her chest artificially using hormone pills. It works at first, but soon backfires spectacularly, as she keeps getting bigger and bigger and eventually gets so big she becomes a laughingstock.
• In "Savage Breasts", part of an anthology called Smart Dragons, Foolish Elves, a woman gets a mysterious exerciser to make her bosom larger...but her enlarged breasts have a mind of their own.
• An especially extreme example happens in one of the many Xanth books. Grey, a protagonist of a previous book now given a supporting role, is helping a female golem create a human female disguise. The golem is able to manipulate the disguise to her liking, but needs Grey's input on what normal human proportions are. Things go well for a while, but they arrive to the golem's bust size and she asks Grey to tell her when to stop making them grow. The problem is she makes them grow a cup size every second and the easily flustered Grey just stands their gaping as golem's breasts get bigger and bigger. Eventually they get so big they threaten to fill the entire room, fortunately Grey is able to yell to the golem to shrink them back down before he suffocates.

Live-Action TV

• An episode of 1000 Ways to Die includes the story "Titty-Titty Bang Bang," an apocryphal story of a woman whose botched boob job started expanding out of control, eventually exploding and killed her.
• One of the first Imagine Spots in Ally McBeal is of Ally's breasts growing until they snapped the bra straps.
• Kitty gets a boob job offscreen on Arrested Development—and then repeatedly tells Michael to stop looking at them. Even when she's exposing them.
• Attack of the Show! has a spoof of home exercise equipment and breast enlargement remedies called "EasyCurves".
• The Benny Hill Show:
  • A sketch depicts an harassed young woman at a bus stop suddenly transforming into She-Hulk. The early stages of her transformation memorably show her flat chest (under a T-shirt bearing the legend LUDO) expanding and EXPANDING... until eventually, the word LLANDUDNO is stretched amazingly tight over her ballooning bosoms. Only THEN is a loud ripping sound heard. Disappointingly, when we then see her transformed, while she's undeniably attractive, her balcony just doesn't measure up...
  • In another sketch, Benny plays a man helping a woman pump a flat tire on her bike. Instead of the tire inflating, her breasts grow. Cue Aside Glance.
• In the Charmed (1998) episode "Hell Hath No Fury", Paige's breasts expand due to using magic for personal gain.
• The Collector: In the third episode of the first season, a svelte supermodel rejoices when she finds her breasts swelling to massive size, but expresses grim dismay when the same thing happens to her ass.
• One episode of Everwood featured a cheerleader who had her breasts surgically enlarged to make herself more popular but she soon suffers from complications from the operation. The main character (a doctor) says they have to go, but she's so desperate to look bigger she initially refuses, thinking she'd be humiliated.
• Subverted in House: House suggests breast enlargement as a convenient explanation for the scars from a diagnostic surgery when the patient (an Air Force pilot who wants to become an astronaut) insists that the team do nothing that would make NASA's doctors suspect she had health problems. When asked why not breast reduction, he points out that she'd be an unlikely candidate.
• A somewhat complicated example (except for the viewer) occurred on the German sketch show Klimbim. In a SF setting, the bratty pre-puberty daughter says she has bought bionic boobs - and proudly shows them. (The player of that character is an adult woman, so they are her real own ones.)
• In Mighty Morphin' Power Rangers specifically with the pink ranger. While Yellow was played by a man Pink was played by a female. In sentai footage her chest is rather flat but in American footage her breasts are noticeably more pronounced.
• An early nineties cop drama, Pacific Blue, featured an episode where teen girls were dying because they were having silicone injected into their breasts to make them bigger, with the help of a disgraced former plastic surgeon. They were financing it by stealing cars. Truth in Television: in the early days of plastic surgery, this method of breast augmentation was somewhat common, and obviously quite deadly, yet it didn't stop anyone from trying. Yes it was that important to them!
• An episode of Popular had one girl trying to make herself look larger with an overinflated pump-up bra...with LOL-worthy Epic Fail results.
• In an episode of Roseanne, the title character is scheduled to undergo a breast reduction to help with her back problems. She dreams that the doctor, Doogie Howser, actually made them larger. When she complains that the surgery went wrong, he innocently asked, "What's wrong? Not big enough?"
• An episode of Sabrina the Teenage Witch featured the character Hilda Spellman after she suffers from a breast expansion after wearing clothing trapped with a Booby-Trap spell. Sabrina then unknowingly wears the sweater and suffered from the spell also to the amusement of Salem.
  • A later features main character Sabrina having her breasts magically enlarged by a photoshop-like program she's trapped inside of. After she gets out of the program, she can't reverse the transformation.
• Scrubs has this in the episode Their Story, in which The Todd had become a plastic surgeon, and convince Turk to let him perform this surgery on a 16 year old. In the end, by introducing him to the girl who explained why she wanted it in the first place.
• An interesting male example is the three Ferengis fantasizing about getting "lobe expansions" from the sales of Seven of Nine's nanoprobes in the Star Trek: Voyager episode "Inside Man".^note  In Ferengi culture and anatomy, the lobes are an erogenous zone roughly on par with the human penis or testicles. Thus, the Ferengi obsession with them and their enhancement.
• That's My Bush!: Bush's Dumb Blonde secretary tries to increase her intelligence by buying memory pills, but she gets mammary pills instead. Flight Of The Valkyries plays during her ultimate bust-out, which also saves her and her coworkers by breaking her free of her ropes.
• In Will & Grace when an old crush of Grace's with a fixation on large breasts gets in contact with her she wears a water-filled bra to inflate her breasts with predictable results. When the guy turns out to be a jerk it gives her a unique way to wreak revenge on him however.

Music

• David Brody's Make My Boobies One More Size.
• The music video for The Giver by Duke Dumont has Jesus grow a roller skater's breasts to the point they're bigger than her head.
• I Must Increase My Bust by Lords of Acid.
• The 18+ music video for the Russian pop song "Caviar" by St.Olie (Ilona Stolie's music project, who also made "I Will Burn...") features this. After the main character's one-night stand gets replaced by a bicycle pump, she uses the pump to inflate her empty mini-fridge into a very tall high-quality fridge fully stocked with caviar and Coke bottles. After spilling some near her tiny breasts, she pumps herself until her breasts become downright huge and then she becomes a model, surrounded by luxuries she inflated from squalor. At the end of the music video, she gets deflated by a rival model who steals the pump, turning everything the main character inflated into something fancy back to normal. The rival model then inflated her own breasts to the point she popped.
• This homemade music video, judging by the lyrics and images, implies a girl gets breast implants to show off at a beach but dies as a result...somehow.
  • The point of the video could also be that since implants are so artificial, they literally lasted longer than she did.

Toys

• The "Growing Up Skipper" Barbie doll could change from a little girl to a teenager with a twist of her arm — complete with a fuller bust.
• While not "real", exactly, one issue of Cracked featured a satirical ad for 'Breast Implant Barbie'—a Barbie doll who has had her breasts surgically augmented. Part of the joke was that she could "leak" and deflate, and would need to be pumped back up again.
• A Japanese dollar store Daiso sometimes sells a set of rubber toy Fake Boobs that contain baking powder and a weak citric acid sachet, meant to be worn under a shirt. Squeeze them to break open the acid sachet, and the resulting fizz inflates them. The box instructions, amusingly, indicate that it's the sort of gimmick that is bandied about at drunken parties.

Video Games

• The start of Blaster Master Zero II has the protagonist's formerly petite companion Eve getting infected by a virus which changes her physically, most notably it gives her very large breasts. This is a rare downplayed Played for Drama example considering the character's themselves never comment on Eve's new endowments and the aforementioned virus is threatening her life. They don't go back down even when her infection is stabilized.
• BoxxyQuest: The Gathering Storm had the Dummied Out “Expansion Gel” item, which would’ve upped Catie’s bust size and given her a temporary stat boost. The gel was left inaccessible in the game’s final version, but remains fully usable if hacked back in.
• Downplayed in Galaxy Angel II with Kahlua Marjoram. When she transforms into her Sexier Alter Ego, her bust increases two centimeters, opening up her Angel jacket to show her cleavage (shown in her animated sequence).
• Guilty Gear Xrd -REVELATOR-: Prior to becoming Justice, Aria's original form was quite slender. When her Jack-O' and Justice selves merge, the recreated Aria is shown with a bigger bust than she was originally shown.
• Actually part of the gameplay in Bunny Must Die — Bunny can get a special Playboy Bunny costume that allows her to induce spontaneous Breast Expansion and return to her normal proportions. Getting enormous breasts increases her attack and defense, but reduces her speed and jumping ability.
  • Her default stance is actually based on that form. Otherwise, she's leaning forward for little reason.
• Inverted in the intro of Dragon Age II. Bethany, the Player Character's sister, has huge breasts as does a female Hawke. Once Cassandra tells Varric to stop exaggerating and tell the story how it really happened, and the game starts for real, they're suddenly much more reasonably sized.
• In the Epic Battle Fantasy series, the Cow Costume will enlarge the wearer's breasts by about 25%^note Unless the "Cleavage" setting has been turned off. The effect gets commented on in Epic Battle Fantasy 5:
  Anna: H-hey, I've got decent breasts now!? I can get used to this! Take a look at me now, guys!
  Natalie: W-WHAAA?! What's with this outfit?! What sort of perverted magic is this?
• An unintentional example occurs in Jitsu Squad when you fight Viper. In her first form when she pulls a mouth beam on you, her boobs inflate until they're half her body size!
• Happens with most CPU's in the Hyperdimension Neptunia games whenever they activate their HDD forms. Neptune, one of the main characters, goes from flat-chested to a generous E-cup, for example, while Vert's already big breasts get even bigger. Averted with Blanc, who stays as flat as she was (much to her chagrin) and inverted with Uni, whose breasts actually get smaller. Peashy takes it to an unheard of extreme, going from AA-Cups to I-Cups.
• This is the main premise of the Play Station Vita Roguelike Omega Labyrinth. The story is about a girl hoping to enlarge her breasts is seeking an object called the "Beauty Grail", which lies at the bottom of a monster-filled dungeon. Killing monsters releases "omega energy", which is stored in the player character's breasts, gradually causing them to grow from an a-cup all the way to a k-cup. However, all this energy is lost when you exit the dungeon; presumably the Beauty Grail is needed to make the transformation permanent.
  • It is a key mechanic in Omega Labyrinth Life. Omega Power is effectively experience points, giving your characters the necessary strength to fight the increasingly more dangerous monsters deeper/higher into the dungeons; as it is stored in a woman's chest, the size of their breasts reflects their power level. The maximum is Z cup, "the Forbidden Bust," which gives them the incredibly powerful Omega Slash skill, letting them deal massive damage at the cost of shrinking back to their original breast size from the loss of Omega Power. Fittingly, one of the debuffs is "Washboard," shrinking them to AA-cup, vastly reducing their stats, and removing the ability to use skills and the "Size Up" identification mechanic.
• In Playboy The Mansion: Private Party you build up points that you can use to archive photos or on Cheats. One of these is to instantly give all the women giant breast implants.
• Princess Maker has an item you can purchase known as the Buxomize Pills which do exactly you would expect, though you have to use two of those to have a visual change on the avatar. Other than the Princess expressing delight with her newly expanded bust and some dialogue changes with the other characters, this does not impact gameplay.
  • A Let's Play of Princess Maker 2 takes this straight into Nightmare Fuel territory.
• In the first Ratchet & Clank game, there is an Easter Egg of this. If you stand in front of the lady who starts the hoverboard race in Blackwater City and then do multiple flips, her breasts will slowly enlarge for every flip until they become ridiculous in size.
• Ryōbi from Senran Kagura is normally flat-chested with the usual angst that follows. Her transformation, however, gives her a fairly sizeable pair, more in line with just about all other characters.
• In Spellcasting 301, one of the challenges is a wet t-shirt contest. One of the two things you need to do in order to win is to recruit a very flat chested girl and cast the UPPSSY (reverse condition) spell, which makes her improbably stacked.
  • In the first game, there's a spell to explicitly increase bust size... but rather than using it to enlarge breasts, you use it on a stone bust of the school's founder, making it bigger so you can climb into the school's stacks.
• In Tech Romancer, one character named Polin appears to be a young girl who uses her magical abilities to transform into a tall, buxom teenager. She actually gets into an argument with another character over who has bigger boobs.
• In Touhou Project fanworks, BE is the dream of several of the rather under-endowed girls, including Sakuya and Youmu. Numerous ways to achieve this end exist, from suspicious mushrooms picked by Marisa to Eirin's shady drugs.

Visual Novels

• In The Pirate's Fate the main character Mila finds a magic coin that can transform her, her new form varies on what choices you have made: for example being aggressive will increase her muscle mass whilst being kind makes her fatter. However, all these various transformations do have one thing in common: they all make Mila's breasts bigger. Oftentimes much bigger.
  • Can also happen to other characters depending on the path taken. The most notable being when the thief Tam-Tam takes a coin from a statue dedicated to a goddess of beauty. After taking the coin, Tam-Tam's already fairly big breasts grow to a truly tremendous size. Whether or not this is a curse or a blessing from the goddess is debated amongst the characters.
• In the Time Tenshi series, this is one of the main side-effects that occurs when women travel through time. The longer they spend outside their native timeframe, the more permanent their growth is. For example, formerly flat-chested Kyo is one of the characters with the most experience traveling through time. She has grown into a large base size as a result, and is positively ecstatic whenever they grow even bigger. After the first game, Michelle spends weeks trapped in a limbo outside of time, so by the time she's rescued her minimum size is akin to beachballs.

Webcomics

• A defunct webcomic by an artist named "Jae", titled simply ''Amy'', focuses on the eponymous young woman who undergoes a breast augmentation procedure because, as she puts it, "I'm 18 years old, and FLAT CHESTED!" The doctor is so concerned with looking at her ass that he botches the thing, and she's left with breasts rapidly increasing in size... unable to get back in contact with him to fix her new knockers, she has to face the grim outlook of breasts twice as big as her head and still growing.
• There are several pay-for-view webcomics that have Breast Expansion as the major theme, often going under a banner like "BE Story Club", with several different series encompassing different methods and sizes.
• Breast Expansion is one of the powers Prince Albert has over his bratty older sister in Blooming Faeries.
  • Any woman who has sex with Sir Thane, no matter how flat or unpleasant looking they were before becomes beautiful with large breasts.
• Calamities Of Nature features a series of comics in which a character invents helium breast implants so that women can have larger breasts and lose weight at the same time.
• Happens quite surreptitiously in Cyanide and Happiness.
• In the last arc of Darwin Carmichael Is Going to Hell (Comic 315 - Game Over Part x specifically), Ginny's breasts grow dramatically once the apocalypse starts, as the heightened magical energy awakens her succubus blood.
• Eerie Cuties: Invoked twice. The first instance was to demonstrate that succubus puberty can be abrupt at times. The other happened to Prof. Twigget, as a result of the Tiresias Orb bonding with Blair's mind.
• One strip of Ennui GO! reveals that the supposed Fanservice Pack that all the girls got over the course of the series was actually due to the water resevoir for the beer brand that Izzy owns having accidentally been contaminated with an experimental bust-enhancing cream. Izzy mentions in a later strip that this has caused it to become a hit with half of the transgender community.
• El Goonish Shive:
  • Using the "FV5" setting on the TF Gun on a woman makes them taller and curvier. The effect doesn't stack, but using it on someone who's quite busty already can get pretty ridiculous results.
  • Subverted in an old sketchbook comic, where Ellen attempts to invoke her "Wonder Twin Powers"... and fails to increase her bust.
  • Grace is a Voluntary Shapeshifter, and altering her chest size (or anything else) is no big deal to her. She discusses with Sensei Greg whether it's a good idea to go flat if she ever gets in a fight, but he's too uncomfortable to answer the question. Later on, she admits that she changes her breast size to mess with boys at the comic shop.
  • It's later used in the Magic: The Gathering parody, with the "unbalanced" enchantment that stops a fairy from being able to fly.
  • This was one of the things Rhoda tried while experimenting with her Sizeshifter powers. She also briefly considers giving Kitty gigantic boobs to stop her from chasing her and Catalina, but quickly decides that's a terrible idea.
• In Held Within Strip #13 Susie tells her girlfriend Jenny that she first noticed her when Jenny's breathing made it look like her breasts were expanding. Later on in Strip #21, when Jenny starts changing into a genie, her breasts really do expand.
• In I Dream of a Jeanie Bottle, Jean does this to one of Neil's coworkers to reveal her as a spy (It's a long story involving sleep deprivation and Jean's assumptions about female attractiveness).
• In Jix, Lauren (the only human female character) has had this done to her off-screen because Lamerix (the techy character) often uses her as a human guinea pig. Lamerix is testing a breast enhancer device so that she can market it to her alien species. (She figures the male Ambis, her species, would enjoy it and it may make nursing easier.) The real reason, or so the author claims, is to make the female Ambis look more feminine since they were originally designed flat-chested.
• A theme in many of the webcomics by Lightfoot.
  • In (the rebooted) Pulse, super-heroine wannabe Annie Chang participates in an experiment to increase her barely useful natural electrical powers. While the process was successful, the skinny girl develops a super-heroine physique, including boobs that are at least huge. Leaving her embarrassed and awkward about her body.
    • Some of his older, now cancelled comics displayed this theme more blatantly, before he decided he wanted to focus more on the story and characters:
    • In (the original) Pulse, Annie Chang, a former flat chested girl gets superpowers through a Freak Lab Accident and as side effect experiences breasts that grew by noticeable amounts throughout the series. Eventually, her partner makes up a story to the press that she's a robot and the breasts are actually missiles. Annie also has an old friend who initially appears huge, but is in secretly flat and must take a special pill regularly to remain buxom. In the last issue of the original run a scientist was able to secretly drug his female co-worker with a chemical which would cause any excess fat to go to her breasts, and judging from her increased appetite she may not be unaware of it.
    • (co-written by Wolfman 1066) Peeveed dealt with a down on luck main character, named Eve. Things changed when she finds and becomes the master of a female genie thats obsessed with big breasts. As with most comedies involving genies Hilarity Ensues and through the course of the series she goes through breast expansion a few times, ironically not once did she wish for bigger breasts. The effect would wear off each time and she would have returned to normal by the next story, Though in one case her flat friend retained her new size.
    • There's also My Big Life. About a reporter who's writing a column about the trend of women getting giant breasts, she does this by getting gargantuan breasts herself and reporting on her experience for a full year. Fortunately, because the series takes place in the future, there's technology available to turn her huge breasts to nothing more than an inconvenience. Any change was implied, her natural body was never shown, nor the process of her changing.
    • In a short Kim Possible fan comic titled 'Possible Envy', Kim and Shego are competing in a swimsuit compitition were they continually try to upstage each other by being blasted with breast expanding ray guns. By the end of the comic no woman in the area escapes without breasts bigger than their head, and at one point bigger than buildings!
    • In two short Teen Titans comics. Starfire and Raven respectively get this treatment. In Ravens case she grew failing to stop the 'prophecy of the giant bra', And Starfire grew massive from some sort of biological reaction from eating pink coloring.
    • His most blatant example of this trope was a Final Fantasy fan comic called Missing Materia. Yuffie gets her hands on a rare materia that causes growth and she abuses often, sometimes just to annoy people, all the while Materia from all over the world is mysteriously vanishing. By the end of the comic nearly every woman effected has breasts so big they can't move.
• Newly minted webcomic Love Me Nice, about the crass Animated Actors of a hit TV show, has one character, Carolina, get breast implants because she looks like a cutesy little Rainbow Brite-ish doll and wanted to be taken seriously by men. Predictably, the opposite occurs.
• As a Christmas wish for Brendan in Pokémon-X, the author does this to May, leading to what may be the first pixelated case of this.
• In Skadi, Skadi and Diseasoid are subjected to a "hotness spell", which turns him into a Top-Heavy Guy and gives her very large breasts.
• In Slimy Thief Aisha's body was merged with a slime creature so now certain parts of her body grow when they touch water. She regards this as a curse but notes that there are some advantages, one of which being that she can make her breasts as big as she wants.
• In one storyline from Sore Thumbs, normally flat-chested Harmony gets breast implants when the busty heroine of the series disappears and she feels she has to pick up the slack. She later had them removed because her friend returned... and because she initially had trouble standing upright under the weight.
• The origin of Spinnerette's "Ms. Venus"/"Super MILF" (seen in marginally-NSFW flashback) involves an alien biological nanoscale tokamak reactor cluster implanting itself in her bosom via a Freak Lab Accident. In addition to the superpowers, this causes immediate shirt-ripping and necessitates a Cleavage Window (to dissipate waste heat).
  • We later see the origin of Greta Gravity, which plays out similarly except for the fact that she puts on weight all over. Still, you can imagine where the focus is.
• The web comic Supermegatopia (a furry world with many superbeings) has their BE mascot in the subtly-named Buxom Gal. Her origin involves a breast expansion experiment carried out by aliens. Afterwards, she is left with standard superpowers (superstrength, flight, ability to fire power bolts), but discovers that - if she does not use her powers - her breasts (which "store" the energy for these powers) expand to incredible size, with incredible speed.
• Wapsi Square: Siren puberty works much like succubus puberty in the preceding example. Which makes it a cause of concern for 15 year old Atsali, since Sirens are commonly believed to have as sexual predators.
• in The Whiteboard, a pot of Klatchian Coffee grants the women who drink it a temporary increase of their bust size.

Web Animation

• I'm Anton!: Peter's mother was flat-chested so Peter tried to find ways to enlarge her breasts so he can have a new father. Peter met a shady guy who gives him cow steroids which he slipped into his mother's food, resulting in her breasts growing. She freaked out at first and asked Anton's company for help but after Peter confessed everything, she accepted and eventually got remarried.

Web Original

• Mordred from Fate/Nuovo Guerra got this as part of her Gender Bender package from the Holy Grail. ^note To clarify, due to being a clone, he was inserted into a Servant body based on his mother Arturia, only a couple of sizes bigger.
• In the "Amplified Bible" episode of the Foamy the Squirrel animated web series, Foamy casts a spell from the book Bigger Boobs Through Witchcraft on his pet human, Germaine. Her chest swells enormously — a fact neither of them realizes until the next episode where they are so big she can't get sit up, and they still kept growing. The spell seems to have lasting effects, as Germaine's breasts are noticeably larger in the later Foamy episodes than they had originally been. Much to her chagrin.
  • In the episode "A change of Heart" after her breast reduction surgery Germaine expresses an interest in A magic ring that lets her control her breast size. Foamy points out it defeats the purpose of her reduction, to which Germaine replies she only hated them because she couldn't turn them off when they didn't benefit her, having grown to rely on them for big tips and discounts from horny men. She later plays with the ring in the bath, making her breasts bigger and smaller via putting on the ring, and at one point makes them so big that her stalker's head explodes at the sight. As of "Big Tips", she is actively using the ring to make her breasts large while at work to make back the tips she lost.
• In the Paradise setting, humans are being randomly, permanently changed into Funny Animals (and sometimes gender-changed at the same time). In keeping with the Wish-Fulfillment inherent in the setting, female Changed receive an extra helping in the endowment department over what they had as humans—and those who used to be male humans get even more.
• Skippy's List (whose creator and protagonist is male, by the way) has the following example:
  5. Not allowed to get silicone breast implants.
• In the Smosh video "Magic iPad", Ian uses the titular tablet to make his date's breasts larger.
• This Star Trek: Voyager video in which the crew try to solve the crisis of the week: Seven of Nine's randomly expanding breasts!.
• Since the Whateley Universe features a significant number of mutants whose "body image template" endows them with superhumanly good looks, it's probably a safe bet that quite a few mutant teenage girls are going through this while changing. There's also a humorous, if slightly squicky, example in one of the Jade stories where one of Jade's autonomous telekinetic constructs gets herself equipped with artificial inflatable breasts operated by remote control to help her serve as an icebreaker at a party.
  • Rather less humorous (for Phase) was when Belphegor sabotaged a serum made by Jobe Wilkins with the intention of reversing Phase's Gender Bender status. Unfortunately, not only did it fail, it failed spectacularly: his breasts, rather than shrinking, grew to epic proportions, and continued growing for several hours while Jobe worked to reverse the effect.
• One YouTuber animated the “New Anime Plot Copypasta” by showing the bishounen’s breasts expand every time a nonsense word is said.

Western Animation

• On an episode of 101 Dalmatians: The Series the villainess, Cruela De Vil, tries to seduce Roger by putting on a blonde wig and using inflatable fake breasts. Not only doesn't it work she ends up bouncing so much she literally bounces away. This was a children's show mind you...
• American Dad!:
  • In the episode "Tearjerker", a James Bond parody, when Stan and Sexpun (Francine) are tied, Stan remembers that Sexpun has a ring in her pocket that was given to him by "S" (Steve), whose gadgets only make womens' breasts grow. He urges her to put it on, which causes Sexpun's breasts to swell so large that they break the ropes, allowing her to set herself and Stan free. Of course, it should also be noted that S designed all his gadgets to make breasts bigger, and expressed confusion when Stan asked for items that might have more practical use in the field.
  • In another episode, Stan gives Steve hormone pills in an attempt to get him in with the Jock crowd; unfortunately, he mistakenly grabbed the female hormone pills, which results in Steve growing a rather large pair of breasts. As a result, he still gets in with the Jocks, but only because they want to ogle his chest (and later grope it, which he's totally okay with). Steve refuses to get rid of the breasts because he's convinced the Jocks like him for his personality, but Stan disproves this by showing up at a party with even bigger breasts (having taken a double dose of the hormone pills) and instantly stealing all the attention away from Steve.
    • Pretty much that exact same plot happened 2 years earlier on Hey Joel. Just replace hormones with bulk up powder and jocks with Bill Wyman.
• In the Braceface episode "Busted", central character Sharon buys a pump to make herself bigger. She ends up overdoing it, with humiliating results. First getting laughed at by the same people she was trying to impress, and then her boobs... pop.
• One episode of Duckman involves a brief trip to a plastic surgeon, where we see a woman inflating her breasts with a compressed air pump until she explodes. Another featured a short gag about a ray that makes breasts triple in size, as a background gag.
• Family Guy:
  • Peter asks Jesus to give Lois huge breasts and in the next scene Lois' boobs grow to absolutely enormous size.
  • Another episode had Lois stop breast-feeding Stewie, and her breasts got so big she was popping buttons off her shirt— just in time to save Quagmire from a bad marriage by reminding him just how much he'd be losing...
  • Peter remembers how much he misses Lois, and he draws a quick doodle of her on a napkin. Then, he erases her chest and redraws it by several sizes.
• Rick and Morty: In "The Whirly Dirly Conspiracy", Summer's boyfriend dumps her for a girl with bigger boobs, so she uses one of Rick's devices to give her a bigger cup size. It works, until she accidentally goes too far on one side, over-corrects the other, then trips and gets caught in the beam and turns into a mishmash of flesh.
• Robot Chicken:
  • In the "No Need for Glomer" sketch of the animated version of Punky Brewster where Punky asked an abused Glomer to make her boobs bigger that went all the way into Body Horror. This is Very Loosely Based on a True Story. Actress Soleil Moon Frye, who played Punky Brewster in both the live action and animated series, suffered from gigantomastia and had breast reduction surgery when she was 15.
  • In another sketch, The Bionic Woman is in an accident and needs repair. The Six Million Dollar Man gets the scientists not only to fix her but upgrade her... into a literal sex machine. Including giving her enormous breast implants. Needless to say, she isn't pleased and beats the men... with themselves.
• The Simpsons:
  • In the episode "Large Marge", Marge was accidentally given breast implants instead of liposuction and protests to the doctor.
    Doctor: [bored] Yes, I'm sure your husband will be furious.
  • In the episode "'Tis the 30th Season", a heavily pregnant Brandine Spuckler is in a Black Friday line and doesn't want to lose her place on account of birthing her baby. She sucks in her gut so much, her breasts grow as a result, much to the surprise of Lindsay Naegle and the man behind Brandine in line.
• In the South Park episode "Bebe's Boobs Destroy Society", Wendy gets jealous of Bebe's boobs because they've captured all the boys' attention, and pays $3,000 to get hers augmented... Only to find when she returns to school that the boys have gotten over their fascination with them, thus leaving her with ridiculously large breasts. Especially considering she's roughly eight or nine.
• In Stripperella this happens to the title character when she gets shrunk and the nerds try to return her to her original size. They overshoot considerably.
• In one episode of Totally Spies!, Alex takes a muscle-enhancement drug to defeat a villain, which also causes her breasts to visibly grow several times larger (Although at one point she did appear to have a completely masculine chest). Some also point out that the Art Evolution made the girls "powers" more obvious too (considering how fanservicey the show is… quite probable).
• Ugly Americans "Demon Baby": Callie's breasts swell when she comes near the demon baby that Mark is caring for. Then they start to lactate fire.
  Mark: Um, did your boobs just grow when you touched the baby?
  Callie: No.
  Mark: Are you sure? 'Cause I could have sworn. There, it happened again.
  Callie: Stop staring at my boobs.
  Mark: I can't, so I'll go.
• On the series the comic book is based, W.I.T.C.H., the characters transform into Guardians granting them wings, power, and a temporary instant puberty growth - which includes growing larger breasts. The typical fan-service associated with this trope is Downplayed but the difference in breast size is sometimes addressed or used as a plot device.
• Sgt. Hatred of The Venture Bros. grows breasts throughout season 5. His first assumption is to blame the radiation that caused freakish mutations in a bunch of interns, but that turns out to be coincidence. The real culprit is his anti-pedophilia medication interacting with the Super Serum that caused his pedophilia in the first place. He handles the development rather well, until the breasts suddenly vanish before season 6.
  Sgt. Hatred: All right, all right. See these man-boobs here? Well, they kinda turn me on. Sometimes I look at them when I masturbate and pretend they're on a lady. There. That's a death confession.
  Dr. Venture: I can beat it!

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