History PlayingWith / BrotherSisterIncest

** Alice and Bob aren't siblings; people only think they are because of a misunderstanding.

* '''Subverted''': Dana claims Alice and Bob sleep together, but the viewer later learns that she's just spreading nasty rumors about them as slander.

** Alice is in a SiblingTriangle with [[TriangRelations her two brothers]].

** Their baby's disabilities mean the kid also gets [[DisabilitySuperpower awesome superpowers, which make up for it]].

** ChildhoodFriendRomance
** FirstGirlWins taken up to eleven.

** Alice and Bob are HumanAliens who never evolved an equivalent of the [[https://en.wikipedia.org/wiki/Westermarck_effect Westermarck effect]].

** Alice and Bob hate each other, far more than simple sibling rivalry, and [[CainAndAbel are trying to kill each other]].

* '''Subverted''':
** Bob and Alice do have some initial chemistry--but luckily Charles appears, and the real romance between Alice and Charles starts (a la ''Franchise/StarWars'').
** Alice and Bob like each other, but every time it seems like they're going to get together, something happens. After a long string of increasingly improbable events occurre, they decide [[ThereAreNoCoincidences maybe siblings really shouldn't be together, and that the universe won't let them]]. So they stop trying.
** Dana claims Alice and Bob sleep together, but the viewer later learns that she's just spreading nasty rumors about them as slander.

** But it turns out that [[SurpriseIncest Charles is related to them too!]]
** After they give up, a series of improbable events leads them together again. They take this as the universe's blessing, and go ahead.

** Dana ''did'' make up and spread nasty rumors that Bob and Alice were twincestuous--how was she to know [[AccidentalTruth it was true]]?

-->'''Bob''': I know society will never accept us... but I don't care...

** The doctor informs them that their baby is unhealthy because it was born prematurely, and that inbreeding had no factor.
** The baby manages to overcome their short comings as they grow older, proving that they were not as unhealthy as feared.

** Alice sexually abused Bob since his childhood (or vice versa).

* '''Exploited''': Bob is a corporate CEO, and his competitor, Dana, lets the story loose, intending to ruin Bob and remove her competition.

** Bob and Alice are [[FlirtyStepSiblings step siblings.]]

** FirstGirlWins taken UpToEleven.

** Dana might be trying to hurt Alice and Bob with the rumors, but that doesn't mean she made it up…

-->'''Bob''': I know society will never accept us… but I don't care…

-->'''Alice''': Bob, this is wrong… we're brother and sister… nobody will ever understand…
* '''Conversed''': "That's disgusting. I can't believe that sicko Bob is doing… ''that'' to his sister. His '''sister'''!"

You can go back to BrotherSisterIncest if you like, but… seriously, that's just wrong…

** Alice turns down Bob's advance for reason other then their familiar relationship.

* '''Played For Drama''': Alice and Bob's story is told through a combination of SympatheticPOV and non-sympathetic [=POVs=]. Sometimes it seems like Alice and Bob are StarCrossedLovers, and other times it's just {{Squick}}, leading to a complex and angsty story.

** Alice turns down Bob's advance for reason other then there familiar relationship.

* '''Exaggerated''': Alice is in a SiblingTriangle with [[TriangRelations her two brothers]].

* '''Played For Laughs''': Bob and Alice's parents grill him just like all of Alice's new boyfriends.

* '''Enforced''': It's based-on-history work, about culture that Brother Sister Incest was common in. It's nothing more than the author [[ShowTheirWork show that he did some research]], though in interviews he admits that he finds it weird and would rather have not included it.

* '''Downplayed''': Bob and Alice are [[ChastityCouple dating, but don't sleep with each other]].

** FirstGirlWins

** Bob and Alice do have some initial chemistry--but luckily Charles appears, and the real romance between Alice and Charles starts (a la ''StarWars'').

* '''Exaggerated''': Alice is in a SiblingTriangle with [[TriangRelations two brothers…]] who are also ''her'' brothers.

* '''Exaggerated''': Alice is in a SiblingTriangle with two brothers… who are also ''her'' brothers.

** Alice and Bob are {{twin|cest}}s, and are considered to be born married by their culture.

** Alice and Bob date, and when they break up Alice begins dating Charlie and Bob begins dating Diana. [[BigScrewedUpFamily Who are also Alice and Bob's siblings]].

* '''Defied''': Alice [[{{Squick}} rejects]] Bob's advances.

* '''Doubly Subverted''':

** GenderFlipped or Gender-Inverted as Sister-Brother Incest.

* '''Parodied''': Their parents make a wager to see how long it will take for [[EverybodyKnewAlready Bob to get into Alice's pants]].

** Alice becomes pregnant, and the baby exhibits all the health problems associated with inbreeding, such as mental retardation and genetic diseases.