History Main / Twincest

* ''Fanfic/AnEmpireOfIceAndFire'' already has the canonical example between Jaime and Cersei, but the oneshot sequel ''Something About Dragonstone'' also reveals that Jon and Daenerys' twin children Rhaegar and Arya have entered into a relationship during the TimeSkip. Being [[IncestIsRelative Targaryens]], everyone just shrugs this off.

* ''Film/HellboyIITheGoldenArmy'': Okay, the twincest doesn't actually ''happen'', but boy, does Prince {{Bishonen}} Faerie want it to. It could be inferred that it had happened in the past. Considering that anything felt by one is felt by both, it's likely any masturbation experienced by one would automatically be shared with the other.

If the twins have a child together, that may be known as tw[[IncrediblyLamePun inbreeding]].

* In ''Forced Perspectives'' by Creator/TimPowers, two of the members of Conrad Chronic's cult were a married couple who secretly were twins who had left their home state far behind and faked new, unrelated identities for themselves so they could get married, because their TwinTelepathy left them feeling that they couldn't really connect to anyone else.

* In ''Manga/{{Monster}}'', there is a one-sided example with Johan Liebert and his twin, Anna. Unfortunately, Johan is also [[MagnificentBastard really]] [[TheAntichrist scary]] and effectively scares Anna half to death whenever she thinks about him. Although, [[KillEmAll considering how he treats other people]], this may be the only way he's even capable of displaying affection whatsoever. It doesn't seem to be brotherly love, though, when he talks about her as his "other half". It comes off as a really creepy infatuation, usually.

* It was heavily implied in a few issues of ''ComicBook/InfinityInc'' that Obsidian has a crush on his long-lost twin sister Jade. She was blissfully oblivious. It should be noted that in the original ''ComicBook/InfinityInc'' comic, there's no indication of Obsidian being gay. He, in fact, has a girlfriend in later issues. It wasn't until his and Nuklon's appearances in ''ComicBook/JusticeLeague'' that his sexuality is hinted at, but not confirmed at the time.

* ''Creator/MarvelComics'': The Fenris twins (Andrea and Andreas Von Strucker) play with this idea--and likely, each other!--fairly frequently. And then it got worse gets worse. [[spoiler:Andrea has since died, and since their energy blast powers relied on them touching to function, her brother had her skin made into leather and [[DoesThisRemindYouOfAnything wrapped his sword hilt with it]]. On top of that, he is nothing short of fanatically obsessed with finding a way to resurrect her.]] The whole thing is portrayed just as creepily as it sounds, with even other characters around him being {{squick}}ed by it. Their Ultimate versions were pretty much the same, save for the bit in spoilers. However, when Andrea is later cloned, her brother tries to deny that their relationship was ever incestuous. He allows her to sleep in a separate bed, and claims that while he knows his [[ComicBook/{{Thunderbolts}} teammates]] think that he's a freak, he has no actual desire to have sex with his sister. Then due to some very complicated developments, Clone Andrea and Andreas both died. But then they were back as usual running a nightclub for supervillains, and it was unclear again. After years in limbo, it was finally made canon in JSA.

** Queen Cersei and Ser Jaime Lannister ([[FanNickname the Lannincest]]). An unusual example of an incestuous relationship in serious fiction, as their affection for each other is depicted as genuine, unforced by either partner, long-term, and stable... at least when the story opens. [[spoiler:Jaime is revealed to be the true father of Cersei's children, thus making them false heirs to the throne. This eventually causes civil war to break out, and the situations it puts Cersei and Jaime into gradually begin to force them apart.]] It only gets worse when it's revealed that they were into each other even as little children--their mother's maid saw them doing something sexual shortly before their mother's death, and Joanna Lannister died when they were ''seven''. In Cersei's mind, the bond goes back to their ''birth'', seeing as the two shared a womb and Jaime came out holding onto Cersei. Some readers also think that narcissistic Cersei sees their relationship as the closest she can get to ScrewYourself.

* Lucjan and Myaja, a brother-and-sister fighting team in ''VideoGame/DragonAgeOrigins'', state that "everything they do, they do together." When the PC asks them if that means ''everything'', Myaja asks if he wants to find out.

* A rather bizarre example in ''VideoGame/Drakengard3''. [[spoiler:One's Disciple (basically a bodyguard and a consort combined) is an OppositeSexClone of herself that she created. The clone is addressed as her "Brother" and while they don't do it in the game, the short stories written for the game confirms that they were intimate.]]

* Dipper and Mabel Pines from ''WesternAnimation/GravityFalls'', due to the fact that they always hug or hold hands, are one another's OnlyFriend until the start of the series, and are incredibly affectionate and supportive of one another (to the point where their Grunkle Stan claims that it's "unnatural" for siblings to get along as well as Dipper and Mabel do). What certainly helps is that they have a dynamic similar to a SavvyGuyEnergeticGirl romance and are TheNotLoveInterest for each other (frequently sacrificing for/defending one another). In the fan community, the pairing is known as "Pinecest", after their last name. However, it’s considered pretty taboo to a lot of fans, primarily because of the show's creator Creator/AlexHirsch freely admitting to be grossed out by it since [[WriteWhoYouKnow Dipper and Mabel are based on Alex and his twin sister Ariel]] from when they were twelve-year-olds. Notably, the show’s official subreddit has outright banned discussing and/or sharing fanart/fanfic of Pinescest.

* From ''LightNovel/InfiniteStratos'' and it's obscure FanDom, there's this [[Fanfic/InfiniteStratosSacredTwins (un)holy fic]]. Rather than picking one of the members of Ichika's UnwantedHarem, the author chooses Ichika's HalfIdenticalTwins… [[BigBrotherWorship who's clearly]] [[BrotherSisterIncest hots for him]]. [[spoiler:The girl in question is TheDragon, M (Orimura Madoka), chosen specifically as OCStandIn in an AlternateUniverseFic. [[FreudianExcuse She has]] [[DarkAndTroubledPast a decent reason though]]]]. It's CrazyEnoughToWork.

* Dipper and Mabel from ''WesternAnimation/GravityFalls'', due to the fact that they always hug or hold hands. In the fan community, the pairing is known as "Pinecest", after their last name.
** However, it’s considered taboo to a lot of fans, so much so that the show’s official subreddit has banned it.

* ''Film/BladesOfGlory'': The twin brother and sister villain-duo of Stranz and Fairchild Van Waldenberg have shared an unusually close bond since childhood and are constantly touchy-feely. They finally fling themselves at each other for a kiss just as the police are hauling them away. Creator/WillArnett and Creator/AmyPoehler were [[CastIncest married in real life at the time]].

* ''Film/IncestTheMusical'' is a quirky, upbeat -- bordering on RefugeInAudacity -- short independent film about high-school twins Alex and Katie getting together.

It's especially common as a way of making CreepyTwins just that much more disturbing, often as a form of VillainousIncest. For {{Yuri Fan}}s and {{Yaoi Fan|girls}}s who became fans at least partly because they see a [[ForbiddenFruit forbidden appeal]] to such relationships, twincest supercharges that part of the appeal. Though twincest is not necessarily homosexual--heterosexual {{Half Identical Twins}} tend to have the highest rate of twincest.

* ''Bloods: Inraku no Ketsuzoku 2'': The Sagemiya family is cursed in that its members are sexually aroused in the presence of another of the same bloodline. Misaki twin brother Shun are both disgusted over this and have sworn to resist the curse. However, Shun loses his composure and starts banging their big sister Kagu. After Misaki finds out, she too gives in to the curse and begins an affair with Shun.
* The Hayasaka twins from ''Manga/BusoRenkin'', while probably not involved in ''actual'' twincest, do act a lot like a married couple, and as kids, used to recite the traditional wedding vows to each other as a game. [[spoiler:This was done by their kidnapper, a woman whom have had an affair with their biological father that was later broken off. After being spending nearly three years with the woman, they suffered a ParentalAbandonment with the "marriage game" being their only happy memory giving them a "us vs the world" codependent mentality similar to the Hitachiin twins]]. Meeting Kazuki Muto helped them become individuals but are still close.
* ''Anime/CandyBoy'' is entirely about ''[[YuriGenre yuri]]'' twincest, in that Yukino does like to tease her sister Kanade quite a bit. There's nothing explicit going on, since Kanade decides to keep a cool outer appearance, although she is obviously enamored with her sister. [[spoiler:Something explicit ''is'' going on by the end. They kiss in the last non-DVD episode.]] The manga also revolves around their romantic, and sometimes sexual, feelings for each other.

** This makes up all the drama in one case. Raita Banba, a high school friend of Kogoro's, had a fiancée named Hatsune Kamon. On the eve of their wedding, Hatsune was killed when the car exploded, and Raita was the main suspect due to his CrazyJealousGuy tendencies. It was later revealed that [[spoiler:they were HalfIdenticalTwins, who were separated when they were babies after a house fire, and the two didn't ''know'' that they committed twincest until Hatsune received a call that the DNA results confirms that. Already ''very'' stressed from the thought of Raita's and her origins ''and'' the fact that she was an IllGirl, poor Hatsune soon fell into the DespairEventHorizon and as a result, she committed suicide. The IllGirl part is important, because Hatsune suffered from Turner syndrome which is what happens when one of the sex chromosomes, either the second X or the Y, is missing or structurally altered. Hatsune is in fact Raita's ''identical twin'' and would have probably been born male.]]

* ''Manga/DNAngel'' features some LesYay between twins Risa and Riku, though mostly in color illustrations. There's a rather eyebrow-raisingly sensual pic of them laying side-by-side on a bed. One shall also note that they get a pinky thread of love together.

* Subverted in ''Anime/MobileSuitGundamSEED'': Kira and his SeparatedAtBirth twin sister Cagalli meet in the first episode, neither knowing they're related. When they reunite further in the series, Cagalli comforts the emotionally ragged Kira. Cagalli also seems to develop a crush on Kira. This taken as a threat by Flay, Kira's screwed-up girlfriend ([[MindGameShip it's not a healthy relationship]]). Further toyed with when Cagalli displays a LuminescentBlush at overhearing Flay admit to her ex-fiance Sai that she and Kira have slept together, and when Kira's adoptive parents Caridad and Haruma (who are aware of Cagalli's identity, [[spoiler:as the mother rescued both twins as babies from the place where their biological parents died]]) show a bit of alarm when Cagalli hugs Kira goodbye. They're informed of their true relationship before things have a chance to go any further.

* ''Anime/MyselfYourself'' has twins Shuri and Shusuke with a particularly strong relationship in the face of ParentalAbandonment, with a later rumor even claiming a more illicit relationship. [[spoiler:Under threat of separation, they run away together near the end]]. The DistantFinale goes on, giving them a strange MaybeEverAfter the end, where they attend a concert of main characters, holding hands. The original game at the same time plays with it, [[spoiler: giving the both twins the other LoveInterest, but at the same time having a scene with Shusuke in the route of his sister, where he confesses to one-sided feelings towards her.]] Nevertheless, despite all the ambiguity, it's still {{Fanon}} among fans.
* The first episode of ''Anime/OsomatsuSan'' parodies this. The characters try to re-imagine ''Manga/OsomatsuKun'' for a modern day audience as an [[IdolSinger idol]], harem show with a CastFullOfPrettyBoys. This includes IncestSubtext between the brothers (mind you they're ''sextuplets'').

** The manga and [[AdaptationalAlternateEnding anime]] swap which girl is the sister and which becomes the girlfriend, which muddies the canon sister dynamic. As a result, which girl is the sister and which is the girlfriend aren't only different from each medium, but this ultimately makes certain major plot points and scenes towards the end of the series differ on the medium.

* ''Manga/{{Saiyuki}}'': [[spoiler:Hakkai's girlfriend Kanan was actually his SeparatedAtBirth twin sister.]] It's not known when they found out, but it was [[spoiler:Hakkai's]] motive for what he did after [[spoiler:she was given up to the demons by the villagers, gang raped, forcibly impregnated, and then DrivenToSuicide.]] And apparently even after they found out, they didn't actually break up or anything.

* It was heavily implied in a few issues of ''ComicBook/InfinityInc'' that Obsidian has a crush on his long-lost twin sister Jade. She was blissfully oblivious. It should be noted that in the original ''ComicBook/InfinityInc'' comic, there's no indication of Obsidian being gay. He, in fact, has a girlfriend in later issues. It wasn't until his and Nuklon's appearances in ''ComicBook/JusticeLeague'' where his sexuality is hinted at, but not confirmed at the time.
* In ''ComicBook/{{Lazarus}}'' Jonah and Johannah Carlyle are sleeping together and plotting to [[TheUsurper usurp the family holdings from their father]]. However when one of Jonah's badly underthought plans goes wrong, Johannah plays the WoundedGazelleGambit and pretends that Jonah betrayed her as well.
* ''Creator/MarvelComics'': The Fenris twins (Andrea and Andreas Von Strucker) play with this idea--and likely, each other!--fairly frequently. And then it got worse gets worse. [[spoiler:Andrea has since died, and since their energy blast powers relied on them touching to function, her brother had her skin made into leather and [[DoesThisRemindYouOfAnything wrapped his sword hilt with it]]. On top of that, he is nothing short of fanatically obsessed with finding a way to resurrect her.]] The whole thing is portrayed just as creepily as it sounds, with even other characters around him being {{squick}}ed by it. Their Ultimate versions were pretty much the same, save for the bit in spoilers. However, when Andrea is later cloned, her brother tries to deny that their relationship was ever incestuous. He allows her to sleep in a separate bed, and claims that while he knows his [[ComicBook/{{Thunderbolts}} teammates]] think that he's a freak, he has no actual desire to have sex with his sister. Then due to some very complicated developments, Clone Andrea and Andreas both died. But then they were back as usual running a nightclub for super villains, and it was unclear again. After years in limbo, it was finally made canon in JSA.

** The twins [[MrFanservice Gemini Saga]] and [[EvilTwin Gemini Kanon]] make one of the most popular and accepted couples among slash and yaoi fans in this series both in the manga and anime because of their dramatic and conflictive relationship as twin brothers who love and hate each other. Fandom, as we can see [[http://saintseiyayaoi.net/index.php?PHPSESSID=dac7ffcda68cb94e14996c299a5a6d73&board=72.0 here]] finds quite interesting the fact of imagine that both share more than "brotherly love" (a.k.a. twincest) during their lives despite of being separated during 13 years.

* From ''LightNovel/InfiniteStratos'' and it's obscure FanDom, there's this [[Fanfic/InfiniteStratosSacredTwins (un)holy fic]]. Rather than picking one of the member of Ichika's UnwantedHarem, the author choose Ichika's HalfIdenticalTwins… [[BigBrotherWorship who's clearly]] [[BrotherSisterIncest hots for him]]. [[spoiler:The girl in question is TheDragon, M (Orimura Madoka), chosen specifically as OCStandIn in an AlternateUniverseFic. [[FreudianExcuse She has]] [[DarkAndTroubledPast a decent reason though]]]]. It's CrazyEnoughToWork.

* The Kongo brothers pairing in ''Manga/Eyeshield21'' fandom has a pretty good following. Agon's a huge narcissist and Unsui is very dedicated to his younger brother. It's not hard to imagine it being a little more then brotherly…

* Twincest runs rampant in the ''Manga/BlueExorcist'' fandom, with the Rin x Yukio pairing taking up almost 50% of all online romantic FanFiction (and normal boy x girl pairings less than 25%). Interestingly, there is no hint of yaoi in the actual series (especially since Yukio and Rin's relationship is… bad and getting worse mostly on Yukio's side). In fact, chapter 74 appears to have Kato half calling people out on it… she seems to be doing her best to remind the fans that this [[ShipSinking ship sank]] long ago (and never was there in the first place), though it's mostly PlayedForLaughs.

*** ''Fanfic/FirebirdsSon'' Trilogy plays on the Fred and George question; in it George is female and, while they are quite stated to be in a sexual relationship with Angelina and Lee, several characters have commented that the twins mother fears they would run off together. The fact that they are hyper sexual and extremely perverted (with Georgina confirmed to have had sex with Angela, and presumably Fred and Lee in foursomes) gives credence to this theory.

* ''WebVideo/AskThatGuyWithTheGlasses'' and ''WebVideo/TheNostalgiaCritic'' are twins in fics most of the time, with Ask That Guy usually torturing Critic, sexually, emotionally and physically. [[DesignatedMonkey Fun times for all.]]

* [[CreepyTwins The Twins]] from ''WesternAnimation/{{Superjail}}'' have somewhat of a fanbase that interprets them as incestuous based off their narcissism and closeness to each other. Certain lines (such as their "date" joke from an early episode) fueled the shipping, although the vague [[RapeAsComedy porn incident that traumatized them]] has been used by supporters ''and'' detractors of the ship to prove or disprove the dynamic being canon.

* There's Kinkaku and Ginkaku of ''Manga/{{Naruto}}''. The characters aren't major, but if they were their twincest fandom may be higher. However, there have been fanfics in the past, and some fandom--in forums, and during chapter reviews, who toy with the idea, being that the two of them are constantly together, and they say each other's names in ever breath. It's canon that the word Ginkaku has said most in his entire life is his brother's name. And Kinkaku, while normally stoic and composed, manga-wise, flies into rage whenever his brother is seriously harmed. It also appears they stayed together their entire lives, and neither of them ever got married, or had any children. So there's room to toy with the twincest idea, and a few of the fandom has.

* An accidental example occurs in ''[[https://www.fanfiction.net/s/11677577/1/ The Rabbit Returns to ToonTown]]'' due to [[ChildrenAreInnocent childish ignorance]]. Rhoda once caught her four year old twins playing patty-cake, which they learned from black-and-white Toons. It turns out that Toons consider "patty-cake" as a very flirtatious act. This dates back to the 1910s, when Toons were drawn [[NoBiologicalSex without genitalia]] and resorted to patty-cake as a sex equivalent. Amongst younger Toons, it's not as raunchy, but the act still has a sexually charged element to it. After learning this a few years afterwards, Jack and Rose agreed never to mention that incident again.

* The twist in ''Film/BeautifulKate'' is that Kate not only had sex with her older step-brother, but also her actual twin brother, Ned.

* ''Film/CruelIntentions 2'' had a scene where identical twin sisters make out in the shower. This film was originally produced as the pilot episode for a Fox TV series called ''Manchester Prep'', but the series was cancelled before broadcast and so the pilot was "spiced up" for video release. One can safely assume this scene wasn't in the TV version. Rather ridiculously, in the scene the girls claim to only be cousins. This is one of only a handful of sexual scenes involving real-life siblings to appear outside of porn.

* ''Film/TheDreamers'': An American student befriends a [[GayParee Parisian]] brother and sister Théo and Isabelle. They claim to have been been born connected at the shoulder, even though that can't happen with fraternal twins. It becomes more and more apparent that there is something very… [[{{squick}} odd]] about the siblings' relationship--heavily implied, though never explicitly confirmed, at the very least Isabelle was a virgin until Matthew--but our American [[TwinThreesomeFantasy doesn't really seem to mind]]. Everything's fine until someone [[http://en.wikipedia.org/wiki/Paris_1968 puts a brick through the window.]]
* In ''Film/EuroTrip'', Jenny and Jamie get trashed on absinthe and make out (neither realizing who the other is). They are appropriately horrified when they open their eyes, and the next morning.

* ''Film/IncestTheMusical'' is a quirky, upbeat--bordering on RefugeInAudacity--short independent film about high-school twins Alex and Katie getting together.

* A key theme in Film/TheLodgers. The family's ancestors were a pair of twins who fell in love and married. This doomed their children and every generation after to live out a terrible curse: breed and raise the next generation of incestuous twins, then commit suicide by drowning together. [[spoiler:Rachel]] resists this fate while [[spoiler:Edward]] is eager to embrace it. The tension between attraction and repulsion escalates, and the audience begins to wonder how much of the characters' behavior is driven by the curse and how much is driven by forbidden desires.

* Narrowly averted (at least according to {{Fanon}}) in ''Franchise/StarWars''. The viewers (and the characters themselves) are initially led to expect a love triangle between Luke, Leia and Han, but then it is revealed in ''Film/ReturnOfTheJedi'' that Luke and Leia are actually long lost twins. The romance between them is vaguely {{Hand Wave}}d, and the love triangle is instantly resolved.
** However, the novel ''Literature/SplinterOfTheMindsEye'' was written and takes place before their relationship was revealed and so features romantic scenes with the two, as well as a scene in which Luke openly admires Leia's body. Particularly her "seal-curve hips". Apparently ''Splinter of the Mind's Eye'' was George Lucas's plan B if Star Wars wasn't a big enough hit to make ''Film/TheEmpireStrikesBack'', and would have been developed into a movie had there been no money to make the trilogy as hoped. At this point, he had not decided whether or not Luke and Leia would be family or a romantic item, but with all sources taken into context it looks like a pretty clear case of AbandonShipping.
** ''ComicBook/StarWarsMarvel1977'', which also started production long before ''Film/ReturnOfTheJedi'', also features a great deal of subtext early on. There are many, many instances between ''Film/TheEmpireStrikesBack'' and ''Film/ReturnOfTheJedi'' in which either Luke or Leia were trying for a RelationshipUpgrade when they were interrupted by something or other. On a meta level, it was because the writers knew Han would come back and show whether "I know" meant reciprocation, but looking at it today makes it seem like the Force knew these two were twins and contrived to keep them from sleeping together.
** ''Literature/NewJediOrder'' (''Franchise/StarWarsLegends''): The Yuuzhan Vong pantheon includes Yun-Q'aah and Yun-Txiin, sibling deities whose domain includes "love and hate and all things opposite". Their usual titles are either [[HalfIdenticalTwins "The Twins"]] or [[ThePowerOfLove "The Lovers"]]. Thought it's possibly they either aren't twins or aren't lovers, and the Vong just have [[ContinuitySnarl really confusing mythological canon]]--it happens. (For bonus points, a psyop plants a non-humorous meme in the Vong that the Jedi twins Jacen and Jaina are avatars of the twin gods…)

* In the 1969 British comedy ''Some Like It Sexy'', a guy gets into a threesome with twins (played by former Playboy playmates Mary and Madeleine Collinson). After a little while he realizes the girls are paying more attention to each other than him, and when he moves away they don't even notice. He leaves and the girls continue without him.

** It first shows up with Gerridon and Jamethiel, where it looks like VillainousIncest: They were twins, consorts, and the most infamous individuals in the entire history of their people.[[note]]Gerridon made a DealWithTheDevil, and two thirds of the entire population's souls were reaped to pay for his immortality. Jamethiel helped.[[/note]] But as the story goes on, the VillainousIncest gets {{Subverted|Trope}}--their twincest isn't portrayed as wrong or as part of their evilness. It was traditional and culturally sanctioned in their time, and their match was arranged by matriarchs [[BreedingCult trying to breed the chosen ones]].[[note]]Inbreeding is the best way to produce powerful Shanir, and twin marriage was especially valuable for this.[[/note]] But because of their infamy, ever since Gerridon and Jamethiel, their people have ''mostly kinda'' stopped inbreeding--although the Ardeth still do. But because of the old tradition, their people now see incest--at worst--as a bad idea, not ''creepy'' or ''immoral''.

* There's a rather bizarre example in ''Literature/FifthQuarter''. The soul of Bannon is forced to share the body of his twin sister Vree when another man steals his body. Vree goes after her brother's body, and when they find it, they devise a plan that Vree will distract him by seducing him, and Bannon will "push" the interloper out his body. Partway through, Vree realizes that Bannon is [[ScrewYourself more interested in seducing himself]] than in getting his body back, and calls it off.

** Queen Cersei and Ser Jaime Lannister ([[FanNickname the Lannincest]]). An unusual example of an incestuous relationship in serious fiction, as their affection for each other is depicted as genuine, unforced by either partner, long-term, and stable... at least when the story opens. [[spoiler:Jaime is revealed to be true father of Cersei's children, thus making them false heirs to the throne. This eventually causes civil war to break out, and the situations it puts Cersei and Jaime into gradually begin to force them apart.]] It only gets worse when it's revealed that they were into each other even as little children--their mother's maid saw them doing something sexual shortly before their mother's death, and Joanna Lannister died when they were ''seven''. In Cersei's mind, the bond goes back to their ''birth'', seeing as the two shared a womb and Jaime came out holding onto Cersei. Some readers also think that narcissistic Cersei sees their relationship as the closest she can get to ScrewYourself.
** Twins Aelor and Aelora Targaryen were married, which wasn't unusual, since their family practised incestuous marriage regularly. Aelora caused Aelor's death somehow, and she was driven mad with grief over this fact.
%% * Jennelyn, Jeyne and Nym are TwinThreesomeFantasy, not Twincest
* ''Stalking Tender Prey'' by Creator/StormConstantine has, within the first few chapters, a pair of HalfIdenticalTwins who, because they are [[spoiler:hybrids of human, and a very oversexualised variation on the Nephilim, and the only two in the area, and therefore can only express themselves to each other]] get into twincest an awful lot. Although--let's be fair--most of the main characters do bedhop with most of the other main characters. In fact the main antagonist, as [[spoiler:'''the''' fallen angel, effectively satan]] pretty much gets to bonk 98% of the main characters. Repeatedly.

* PlayedForLaughs in ''Series/AnotherPeriod''. Beatrice and her twin brother Fredrick are in love and regularly have sex. One episode has Freud (yes, ''that'' UsefulNotes/SigmundFreud) trying to cure Fredrick of his supposed homosexuality after being MistakenForGay. When Freud sees Fredrick having sex with Beatrice, he feels the treatment worked, and is unphased at Fredrick being with his sister.

* In the final episode of ''Series/ArrestedDevelopment'' its revealed that [[spoiler:Michael's twin sister Lindsay is [[NotBloodSiblings adopted]]. Her almost ''immediate'' reaction to learning they're not related is to try and convince him to marry her. Later Gob--their other brother--comes on to her when he learns about this. She punches him.]]

* ''Series/{{Glee}}'': Heavily lampshaded--though subverted--with Mason and Madison [=McCarthy=]. Apparently the Cheerios have had to tell them that ''Literature/FlowersInTheAttic'' is not a good example for a relationship, and during the "Home" performance in "Homecoming", Mason sings the line "Boy I love my ma and pa / Not the way that I do love you". Kitty explicitly compares them to [[Series/GameOfThrones Jaime and Cersei Lannister]]. Madison's ClingyJealousGirl behavior comes off as very twincestuous, until we find out that it's actually because she's always been a ParentalSubstitute to her brother, since their actual parents are always out performing rather than being parents. Madison and Mason work it out, and she backs off.

* It's impossible to watch Maya and Alejandro Herrera in ''Series/{{Heroes}}'' without thinking about it. [[spoiler:After all, Maya killed everyone but Alejandro and herself during her twin brother's wedding after she learned that his bride to be was cheating on him...]] Probably a RelationshipWritingFumble.

* It took twelve seasons, but ''Series/LawAndOrderSpecialVictimsUnit'' finally went there in the episode "Bombshell": [[spoiler:Guest-star Rose [=McGowan=] played a con artist/swinger who was swindling people with her twin brother--and also sleeping with him because they "share a soul."]] Elliot even calls the trope by name. It was one of the few things that genuinely managed to shock the seasoned SVU detectives.
** The possibility of twincest had been used years earlier with as a RedHerring with a fourteen-year-old pair of HalfIdenticalTwins. It... turned out to be something quite different.

* The show runner of ''Series/{{Riverdale}}'' also worked on ''ComicBook/AfterlifeWithArchie'', and the idea of twincestuous Cheryl and Jason Blosson carried over, even with Jason being a PosthumousCharacter. The ''aesthetic'' of twincest is played with a lot. In the opening scene (their EstablishingCharacterMoment) Cheryl and Jason are framed like a couple: Wearing {{coordinated clothes}}, {{holding hands}}, going on what looks like a OldFashionedRowboatDate, all with a love song paying. Cheryl once describes Jason as her "soulmate". They are seen in a flashback SweetheartSipping. After losing him, Cheryl is referred to as a "Red Widow". There also shades of twincest in Cheryl's interest in Archie, because Archie resembles Jason so much. In episode 10, it's actually called out by name in-universe by Veronica, who attempting to turn around Cheryl's attempt to bully her and the rest of the gang. However, those accusations appear to made up on the spot, out of spite, not based on any actual evidence. And despite this aesthetic, it [[SubvertedTrope seems that they weren't actually a couple]]: [[spoiler:Jason was determined to be with his third cousin Polly.]]

* Definitely played with by John and Edward in ''Series/TheXFactor'', such as their routine to "Oops I Did It Again", which involved a full re-enactment the talky bit between Britney and her love interest from the music video ("but I thought the old lady threw it into the sea at the end of the movie"). For anyone masochistic enough to want to see them in action, [[https://www.youtube.com/watch?v=Dr-p-3CC3AU&feature=related here]] is the aforementioned performance.

* Myth/ClassicalMythology: In Ovid's ''Literature/{{Metamorphoses}}'', the story of [[http://en.wikipedia.org/wiki/Byblis Byblis]] and Kaunos is a one-sided case. While Byblis likes him, and admits her feelings, he is completely disgusted by her affection.

** Osiris, Isis, Set, and Nephthys were all quadruplets who fell in love while still in the womb together, forming two couples: Osiris/Isis, and Set/Nephthys. From the Middle Kingdom on, Anubis, god of mummification, was changed from being the son of Ra, to being the son of Osiris and Nepthys.
** In some versions of the myth of the divine genealogy, Horus (called "Horus the Elder" o "Haroeris" to distinguish him) was the fifth of the children of Geb and Nut, and this was a way to try to reconcile older acounts in which Horus was a child of Nut. The interesting part comes with the fragments of the "Pyramid Texts" that mention expresely reciprocal sexual encounters between Horus and Seth, something that influenced later accounts where uncle Seth seduced his nephew Horus the Child (also known as Harsiese or Harpocrates). Evidently, the sexual relationship between Seth and Horus was an acknowledged fact during more than 3,000-year of egyptian religion, even though its details varied.

** On the other hand, it is possible that many divine pairs with gender-paired names (Frey and Freyja, literally "lord" and "lady", Njörd and possibly Njörun, Yngvi and Ingun, Ullr/Ullinn and Ullin, Fjörgyn and Fjörgynn, that's right, just one more "n" at the and and it changes the gender) were originally divine pairs whose names denoted some kind of complementarity, without necesarily impliying any kind of siblinghood. Only later some sort of siblingship was added to their relationship, and given the similarity in their names, the idea of twinship was probably innevitable.

* This trope (along with a helping of CreepyTwins) is the premise of Marina Carr's play ''Theatre/PortiaCoughlan''. Portia is haunted by her twin brother Gabriel, who drowned himself as a teenager; the fact that she's still obsessed with him fifteen years later (and that Gabriel is referred to as "unnatural") hints heavily towards this, so it's no surprise when she reveals that their relationship was sexual. It's a bit more surprising when [[spoiler:her aunt reveals that Portia's parents, too, are half-brother and sister, though neither of them know it.]]
* Part 2 of Music/RichardWagner's operatic ''Theatre/RingOfTheNibelung'' cycle, ''The Valkyrie'', has Siegmund and Sieglinde: Twins separated at birth, who meet as adults and fall in love with each other. It looks like it's setting up to be SurpriseIncest, but then subverted when they realize they're twins, but go ahead anyways. Sadly for them, Fricka--goddess of marriage--is very opposed to twincest and adultery. (Adultery because Sieglinde is married, though it was a forced marriage.) Having a goddess against you is never good news, and Siegmund ends up being killed. But Sieglinde is pregnant, an de gives birth to the legendary hero Siegfried.

* ''VisualNovel/YosugaNoSora'' is the embodiment of this trope with the male lead Haruka having such relationship with his very twin sister Sora. Among the both of them, Sora was shown more crazy and obsessed with her brother as she constantly fantasizes having sex with him and gets jealous when Haruka interacts with other females.

* ''VideoGame/FatalFrameIICrimsonButterfly'', with their whole "becoming one with your other twin". One of the key plot elements of the game is the fact that [[spoiler:the village use to perform rituals in which the older twin would strangle the younger one, who would then become one spiritually with the older twin]] and then they'd get to be togeetheeer foreeveeer. This whole "I want to be with only YOU, [insert other twin's name here]!!" thing happens with pretty much all of the Twin Shrine Maidens depicted in the game, including but not restricted to Azumi and Akane Kiryu, the protagonist Mio and her sister Mayu, and the antagonist Sae with her sister Yae. Sae seems to be the one with the most weirded-out obssession with her sister, since [[spoiler:she seems to all along have fantasized about the day that she'd get to be strangled by Yae]] by the end of the game you find a crystal left by her that is pretty much along the lines of [[spoiler:"Oh Yae, kill me, KIIILLL MEE" like she's getting turned on by the idea.]]
** Not to mention in the promotional comercials, Mio and Mayu are shown in a number of amusingly suggestive poses together. [[spoiler:The strangling pose Mio puts herself in above Mayu at the end of the game in Normal mode is also very suggestive.]]
*** Aaaaand some official art has them sitting together or swiming together in bikinis. [[http://www.cameraslens.com/gallery/albums/userpics/10003/2223.jpg Very…]] [[http://www.cameraslens.com/gallery/albums/userpics/10003/poster.jpg very]] [[http://www.cameraslens.com/gallery/albums/userpics/10003/2425.jpg closely.]]

* Crossing over with the ScrewYourself trope there's Morrigan and Lilith Aensland from ''VideoGame/{{Darkstalkers}}''. Lilith is a shard of Morrigan's soul but she has been given a separate body. Being HornyDevils that survive on pleasure sorta justifies their relationsip.

** The show has a long running gag portraying the Bush twins, Barb and Jenna, as hard-partying ''Girls Gone Wild'' types, often ending with the two of them making out.

** This makes up all the drama in one case. Raita Banba, a high school friend of Kogoro's, had a fiancée named Hatsune Kamon. On the eve of their wedding, Hatsune was killed when the car exploded, and Raita was the main suspect due to his CrazyJealousGuy tendencies. It was later revealed that [[spoiler:they were HalfIdenticalTwins, who were separated when they were babies after a house fire, and the two didn't ''know'' that they committed twincest until Hatsune received a call that the DNA results confirms that. Already ''very'' stressed from the thought of Raita's and her origins ''and'' the fact that she was an IllGirl, poor Hatsune soon fell into the DespairEventHorizon and as a result, she committed suicide.]]
** [[spoiler:In fact her IllGirl status is what made her start her fall. Turns out that Hatsune suffered from Turner syndrome which is what happens when one of the sex genes, either the second X or the Y, is missing or structurally altered. Hatsune is in fact Raita's genetic twin and would have probably been born male.]]

* Invoked in ''WesternAnimation/YoungJustice''. [[UnresolvedSexualTension Superboy and Miss Martian]] go undercover as two twins. While in their disguise they [[FirstKiss make out]], and it takes a while for the latter to transform back into her normal self. Much to the horror of Icicle Jr.

* Narrowly averted (at least according to {{Fanon}}) in ''Franchise/StarWars''. The viewers (and the characters themselves) are initially led to expect a love triangle between Luke, Leia and Han, but then it is revealed in ''Film/ReturnOfTheJedi'' that Luke and Leia are actually long lost twins. Thee romance between them is vaguely {{Hand Wave}}d, and the love triangle is instantly resolved.

* ''Anime/CandyBoy'' is entirely about ''[[SchoolgirlLesbians yuri]]'' twincest, in that Yukino does like to tease her sister Kanade quite a bit. There's nothing explicit going on, since Kanade decides to keep a cool outer appearance, although she is obviously enamored with her sister. [[spoiler:Something explicit ''is'' going on by the end. They kiss in the last non-DVD episode.]] The manga also revolves around their romantic, and sometimes sexual, feelings for each other.

* ''Tayu-Tayu'': In chapter 6, Reiju accidentally overhears someone having sex inside a watermill and decides to see who it is. He's shocked to find that it's [[SchoolgirlLesbians a pair of girls]] and even more so when he sees that it's two of his classmates: Haruka and her twin sister Sayaka. Haruka explains that their relationship started [[SituationalSexuality because most of the local boys their age moved away, leaving them with no alternatives for release besides masturbation and each other]]. Once Haruka and Sayaka started having sex, they soon found it impossible to be in the same room without tearing [[LustObject each other's]] clothes off. So they scissor each other [[ExtremeLibido every chance they get.]]

* Implied when Music/TheVeronicas, a band consisting of twin sisters Lisa and Jess Origliasso, sing "All About Us", a song that, while written by them, was made famous by [[{{Music/Tatu}} t.A.T.u.]], apparently SchoolgirlLesbians. The story goes that the song was originally a demo done by the Veronicas; when they couldn't fit it into their lineup, they handed it over to t.A.T.u. Which is not to say that the Veronicas are not twincestuous as hell--see their propensity for taking ridiculously inappropriate-for-sisters pictures. Seriously. Not to mention their [[https://www.youtube.com/watch?v=Q3gjPMv6DT8 music]] [[https://www.youtube.com/watch?v=QfcEKaePGXA videos]]. No… [[https://www.youtube.com/watch?v=ShQTEUjdBxY&NR=1 THIS]] video. Also this is the [[https://www.youtube.com/watch?v=rUR6tEsBO2o&feature=channel official]] video for the first link… and a little more twincest sexy

* ''Literature/ChroniclesOfTornor'': ''The Dancers of Arun'' features male/male twincest between Kerris and Kel. Oddly, it's portrayed as wholly positive.

* This makes up all the drama in one case in ''Manga/DetectiveConan''. Raita Banba, a high school friend of Kogoro's, had a fiancée named Hatsune Kamon. On the eve of their wedding, Hatsune was killed when the car exploded, and Raita was the main suspect due to his CrazyJealousGuy tendencies. It was later revealed that [[spoiler:they were HalfIdenticalTwins, who were separated when they were babies after a house fire, and the two didn't ''know'' that they committed twincest until Hatsune received a call that the DNA results confirms that. Already ''very'' stressed from the thought of Raita's and her origins ''and'' the fact that she was an IllGirl, poor Hatsune soon fell into the DespairEventHorizon and as a result, she committed suicide.]]
** [[spoiler:In fact her IllGirl status is what made her start her fall. Turns out that Hatsune suffered from Turner syndrome which is what happens when one of the sex genes, either the second X or the Y, is missing or structurally altered. Hatsune is in fact Raita's genetic twin and would have probably been born male.]]

* A AlternateTimeline fanfic for the [=PS3=] game ''VideoGame/InFAMOUS'', in which the twin daughters of [[spoiler:the first game's protagonist and LoveInterest, Cole [=MacGrath=] and Trish Daily]], become twincestuous lesbians; due to the nature of the fic, also possible candidate for FoeYay and PowerOfLove.

In a broader religious or mythological context, this trope can be regarded as OlderThanFeudalism, given the many similar myths in different nations where twincest is directly mentioned or implied in the context of couples from HalfIdenticalTwin gods who are portrayed as appointed to become husband and wife, or as the first people in general.

A subtrope of BrotherSisterIncest. If it's just implied, then it overlaps with IncestSubtext. It's also important not to make mistakes with other BrotherSisterIncest couples, since, due to the popularity of this trope and the idea of a spiritual bond of twins, many "ordinary" couples between brother and sister can imitate many twincest cliché elements. And of course, sometimes even Twincest isn't quite incestuous enough for the writers, and that's when you get ScrewYourself.

* It was heavily implied in a few issues of ''ComicBook/InfinityInc'' that Obsidian has a crush on his long-lost twin sister Jade ([[IfItsYouItsOkay this despite Obsidian being gay]]). She was blissfully oblivious. In the original ''ComicBook/InfinityInc'' comic, there's no indication of Obsidian being gay. He, in fact, has a girlfriend in later issues. It wasn't until his and Nuklon's appearances in ''ComicBook/JusticeLeague'' where his sexuality is hinted at, but not confirmed at the time.

* ''Anime/MobileSuitGundam00'' plays with this too. Whether [[DarkMessiah Ribbons]] [[AGodAmI Almark]] and his "sister" [[DarkActionGirl Healing Care]] qualify as twins is debatable, [[spoiler:both of them being DNA-engineered children with the same sequence]], but Healing seems to show a bit more adoration than is platonic towards Ribbons.

* Myth/EgyptianMythology: Osiris, Isis, Set, and Nephthys were all quadruplets who fell in love while still in the womb together, forming two couples: Osiris/Isis, and Set/Nephthys. From the Middle Kingdom on, Anubis, god of mummification, was changed from being the son of Ra, to being the son of Osiris and Nepthys.

** In "Lokasenna" of the ''Literature/PoeticEdda'', Loki accuses [[ThemeTwinNaming Freyr and Freyja]], the sibling fertility deities, of sleeping together, though it's unclear whether this is "truth" or not.

* ''Film/CruelIntentions 2'' had a scene where identical twin sisters make out in the shower. This film was originally produced as the pilot episode for a Fox TV series called ''Manchester Prep'', but the series was cancelled before broadcast and so the pilot was "spiced up" for video release. One can safely assume this scene wasn't in the TV version. Rather ridiculously, in the scene the girls claim to only be cousins. This is one of only a handful of sexual scenes involving real-life siblings to appear outside of porn; as such, not only is it an R-rated example of GettingCrapPastTheRadar, but it might be an example of the radar being turned off completely.

* [[spoiler:Masako and Kanba]] from ''Anime/MawaruPenguindrum'', sort of: [[spoiler:Masako openly chases after Kanba, but though he cares for her, he doesn't reciprocate.]]

* The first episode of ''Anime/OsomatsuSan'' parodies this. The characters try to re-imagine ''Manga/OsomatsuKun'' for a modern day audience as an [[JapaneseIdol idol]], harem show with a CastFullOfPrettyBoys. This includes IncestSubtext between the brothers (mind you they're ''sextuplets'').

%%* In a similar Creator/{{CLAMP}} example, see Hinoto and her hallucinatory EvilTwin in ''Manga/{{X1999}}''.

* Aleksandr and Aleksandra Ramanov in ''Comicbook/NikolaiDante'' are like this, even taking time out of killing the Raven Corps to make out.

** And the same goes with [[SeparatedAtBirth Separated at birth]] twins Mizar Syd and Alcor Bud from Asgard Saga.

* From ''LightNovel/InfiniteStratos'' and it's obscure FanDom, there's this [[FanFic/InfiniteStratosSacredTwins (un)holy fic]]. Rather than picking one of the member of Ichika's UnwantedHarem, the author choose Ichika's HalfIdenticalTwins… [[BigBrotherWorship who's clearly]] [[BrotherSisterIncest hots for him]]. [[spoiler:The girl in question is TheDragon, M (Orimura Madoka), chosen specifically as OCStandIn in an AlternateUniverseFic. [[FreudianExcuse She has]] [[DarkAndTroubledPast a decent reason though]]]]. It's CrazyEnoughToWork.

* Lucas and Claus from ''VideoGame/{{Mother 3}}'' have been treated in this way.

* A rather bizarre example in ''Videogame/{{Drakengard 3}}''. [[spoiler:One's Disciple (basically a bodyguard and a consort combined) is an OppositeSexClone of herself that she created. The clone is addressed as her "Brother" and while they don't do it in the game, the short stories written for the game confirms that they were intimate.]]

* [[spoiler:Junko Enoshima and Mukuro Ikusaba]] of ''VisualNovel/DanganronpaTriggerHappyHavoc'' are an interesting case, as it's not even hinted at in the game they're introduced. Subtext appears in the what-if light novel ''Danganronpa IF''. It then becomes much more explicit in ''Anime/DanganRonpa3'', with [[spoiler:Mukuro]] being quite submissive and blushing whenever insulted by [[spoiler:Junko]], before [[spoiler:Junko]] violently pulls it out of subtext and into text by slapping [[spoiler:Mukuro]] on the butt (knocking [[spoiler:Mukuro]] to the ground) and doing un-advertiser friendly things to [[spoiler:Mukuro]] with a boot through [[spoiler:Mukuro]]'s skirt. It is not depicted as a healthy relationship at all, as [[spoiler:Junko]] [[DomesticAbuse essentially treats]] [[spoiler:Mukuro]] as a SexSlave of sorts.

[[folder:Web Comics]]