History Main / Twincest

* In ''The Bad Place'' by Dean Koontz, Violet and Verbena Pollard are twins and very... close. But it seems this kind of thing is par for the course in the Pollard family.

* In Donna Tartt's ''Literature/TheSecretHistory'', Bunny Corcoran references this trope when he suggests that twins Charles and Camilla Macaulay, who share an apartment, are in it for less innocent reasons than just to save money. This offends her greatly and leads her to comment, "You mustn't think I'm sleeping with my brother just because I won't sleep with you." [[spoiler:[[DumbassHasAPoint He's right, though]], and it's been going on for years.]]

* Made [[IncrediblyLamePun explicit]] in Music/LeSexoflex's cheerfully NSFW song "Twincest." The music video features male and female twins gettin' it on with their siblings, animated by pornographic embroidery.

The most interesting thing about their relationship is the personal mythology they've constructed around it. They see themselves as a single person in two bodies. Jaime is convinced that "If I were a woman, I would be Cersei," and Cersei likewise thinks, "If I were a man, I'd be Jaime." In Cersei's mind the bond goes back to before birth. Their little pseudo-religion even has a prophesy: that they'll die together just as they were born together.

* ''WebOriginal/{{Rogues}}'': The main character and his twin sister are often accused of this while living in their home village of Teckleville. [[spoiler: In one of the Holgard paths, they actually do unknowingly sleep with one another while at a masquerade.]]

* ''WebVideo/CriticalRole'',
WebVideo/CriticalRoleCampaignOne: Both entirely averted and parodied with the HalfIdenticalTwins Vex and Vax. The topic only comes up once in-series, when Vax is discussing his [[OfficialCouple love interest]], Keyleth:

* Both entirely averted and parodied in ''WebVideo/CriticalRole''. The HalfIdenticalTwins Vex and Vax almost never get shipped with each other in the fandom, and the topic only comes up once in-series, when Vax is discussing his [[OfficialCouple love interest]], Keyleth:
-->'''Vex:''' (clearly jealous) Yes, yes, Keyleth is so [[PrecisionFStrike fucking]] beautiful, I get it.\\

** An ExaggeratedTrope with Queen Cersei and Ser Jaime Lannister. 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. The events of the plot gradually begin to force them apart. But their relationship dates back to [[PuppyLove childhood]], and their mother's maid saw them doing something sexual shortly before their mother's death when they were ''seven''. Their bond carried through to adulthood in a SecretRelationship that's a marriage in all but name, with Jaime revealed to be the true father of Cersei's children.\\
\\

* Weiss and Nero from ''VideoGame/DirgeOfCerberus''.
* Amber and Crystal Bailey in ''VideoGame/DeadRising2''. Then again, they both hit on AnythingThatMoves.

* Made [[IncrediblyLamePun explicit]] in Music/LeSexoflex's cheerfully NSFW song [[http://lesexoflex.bandcamp.com/album/twincest-maxi-single "Twincest"]]. The [[http://vimeo.com/12558920 music video]] features male and female twins gettin' it on with their siblings, animated by pornographic embroidery.

Twincest is '''not''' the same as TwinThreesomeFantasy. Twincest is all about twins screwing ''each other''; in a TwinThreesomeFantasy, the focus is either on the third, non-twin party, or on each other but ''for the benefit'' of the third party. Even with true twincest, sometimes the appeal to viewers comes from the idea of inserting themselves and turning it into the fantasy. TwinThreesomeFantasy is to Twincest as GirlOnGirlIsHot is to QueerRomance.

Twincest often associated with ScrewYourself (when a character has sex with an alternate version of themself). The two don't have any clear link, yet the association suggests that some people view [[InsaneTrollLogic twins as alternate versions of the same person]].

* ''WesternAnimation/RobotChicken''

* In "The D'oh-cial Network", an episode of ''WesternAnimation/TheSimpsons'', the Winklevoss twins make a brief cameo, in which they compete against Patty and Selma at the Olympics. The scene ends with Cameron and Tyler making out.

* ''WesternAnimation/{{Tigtone}}'': The king and queen of Propecia are opposite sex conjoined twins who do have a sex life.

* ''Film/TheDreamers'': An American student befriends a [[GayParee Parisian]] brother and sister Théo and Isabelle. They claim to have 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.]]

Twincest is '''not''' the same as TwinThreesomeFantasy. Twincest is all about twins screwing ''each other''; in a TwinThreesomeFantasy, the focus is either on the third, non-twin party, or on each other but ''for the benefit'' of the third party. Even with true twincest, sometimes the appeal to viewers comes from the idea of inserting themselves and turning it into the fantasy. TwinThreesomeFantasy is to Twincest as GirlOnGirlIsHot is to QueerRomance. They '''can''' overlap if the twins are interested in both each other ''and'' the third party, but that's rare.

A common twist in Twincest -- and in BrotherSisterIncest in general -- is SurpriseIncest: for a couple to fall in love, only to find out later that they're related. (See UsefulNotes/GeneticSexualAttraction.) The fact that SeparatedAtBirth is already a common twin trope reinforces this. How far their relationship goes before they discover this generally depends on whether the plotline is supposed to be humorous or tragic.