History Main / MySisterIsOffLimits

* In ''Manga/GreatTeacherOnizuka'', Kunio Murai is overprotective of his AbsurdlyYouthfulMother[[note]]Only 13 years older than him[[/note]] (and may have a bit of an OedipusComplex), to the point of it being his BerserkButton whenever Onizuka shows interest, and jumping into a lake to interrupt their OldFashionedRowboatDate, [[TooDumbToLive despite not knowing how to swim]].

* In ''Literature/AccelWorld'', Ash Roller isn't fond of the idea of his FriendlyRival Haru[=/=]Silver Crow getting together with his little sister Rin ([[spoiler:who, as a result of complicated circumstances, technically is Ash Roller; she had Brain Burst installed on her brother's Neurolinker]]). That said, [[spoiler:when it looks like Ash might have to be erased from Brain Burst forever to protect Rin from the ISS kit parasitizing Ash's bike]], Ash encourages Haru to be friends with his sister, so long as they're ''just'' friends.

* The only redeeming feature of Dallas Genoard in ''LightNovel/{{Baccano}}'' is his violent reaction to his friends (who, like Dallas himself, are two-bit thugs) ever mentioning his little sister Eve.

* Inverted in ''LightNovel/HighSchoolDXD''. Sirzechs is perhaps the most enthusiastic Issei/Rias shipper of the lot, in a series where even her [[HaremSeries eager harem-mates]] want to see them hook up.

* A reversed example in ''LightNovel/InfiniteStratos'': Chifuyu Orimura, possibly the world's strongest IS pilot, is very much aware of the UnwantedHarem that pines for her younger brother Ichika, but she makes it clear she's not simply letting them just have their way with him. To be fair, she sees Ichika as being her only family. She even has a 'woman-to-woman' talk about him with 5 of the girls. She later regrets this in the OVA when she talks to Yamada-sensei about it since she realizes that [[ThatCameOutWrong because of the way she said it]] -- she had a few beers during the talk as well -- the girls think she's [[BrotherSisterIncest yet another rival for her brother's affections]].

* ''LightNovel/MyNextLifeAsAVillainessAllRoutesLeadToDoom'':
** Keith is an unusual example. He regularly butts heads with his [[NotBloodSiblings step-sister]] Catarina's fiancé Geordo and is working to have the engagement called off. The reason however is because [[BigSisterAttraction he is in love with Catarina and wants to marry her himself.]]
** Alan considers his fiancée Mary to be like his little sister and confronted Catarina over her supposed seduction of Mary. This however goes away completely after Alan falls in love with Catarina.

* Played straight in ''LightNovel/{{Oreimo}}''. Both Kyousuke and his friend Kouhei more or less tell each other they're not okay with anyone dating their respective sisters. In Kyousuke's case, it's likely because he feels Kirino's not old enough to date yet (she's 14), and in Kouhei's case, he's got hints of BrotherSisterIncest with his sister Sena.
** Inverted example with Kyousuke's sister Kirino, who gets [[ClingyJealousGirl extremely jealous]] anytime she sees him hanging out with a woman other than herself, especially his ChildhoodFriend Manami. It gets to the point where she brings home a boyfriend in volume 7 of the light novel, and lets him experience how she feels whenever she sees him with his female friends. [[spoiler:It turns out that the boyfriend was just faking it along with her to go along with [[OperationJealousy her plan]].]]
* ''LightNovel/ThePetGirlOfSakurasou'':
** Inverted with Jin and Fuuka. He started dating her because he didn't feel he was worthy of being with her sister, Misaki, the one he really loved. Fuuka realizes this and breaks up with him, telling him to man up and confess his feelings.
** Played straight (though gender and age inverted) with Yuuko, Sorata's [[AnnoyingYoungerSibling annoying little sister]]. She has a BigBrotherAttraction and becomes a ClingyJealousGirl when he's around his female friends.

* [[PsychopathicManchild Jeremy Agriche]] of ''Lightnovel/TheWayToProtectTheFemaleLeadsOlderBrother'' is extremely possessive over his older half-sister Roxana, to the point when he tries to kill Cassis Pedelian more than once after Roxana asks their father for Cassis as her (implied) SexSlave. Later he attacks other people for just looking at her or mentioning her name.

* In ''Anime/YuriOnIce'', Michele Crispino has this attitude towards any man who so much as ''looks'' at his sister Sara, which stems from how boys used to bully Sara when they were younger. Unfortunately, Sara really wants to be able to date and finds her brother's behavior possessive and limiting.

* Subverted in every adaptation of ''Manga/FullmetalAlchemist'' where a one chapter side story, and [[FillerArc one episode]] in [[Anime/FullmetalAlchemist both anime adaptations]] had Armstrong introduce his sister to Jean Havoc, when the latter complained of not having a girlfriend.

* In the ''Literature/{{Brotherband}}'' book ''Slaves of Socorro'', [[ParentalSubstitute Thorn]] and [[DeterminedWidow Karina]] go to a village festival together (Karina insists it's as friends). The next morning, Thorn nervously has a talk with Hal, assuring him that no funny business occurred between him and Hal's mother. Hal finds the incongruity of the situation amusing and reassures Thorn that if he and Karina want to court, it's completely fine with him.

[[caption-width-right:350:"And then my [[OverprotectiveDad dad]]! And then my [[MyBelovedSmother mom]]! And then my second-degree cousin..."]]

While the title says "sister," variations of it also include [[YourMom mothers]] and other female relatives (such as cousins), and for girls, the GenderFlipped "My ''Brother'' is Off-Limits." This doesn't include daughters or sons, because OverprotectiveDad and MyBelovedSmother, respectively, already cover those. Exes fall under TheBroCode instead.

* ''Manga/DeathNote'': When Touta Matsuda shows interest in Light's sister Sayu, who has grown into quite the cutie, no one is thrilled. [[PapaWolf Specially, Matsuda's boss Soichirou... her]] OverprotectiveDad.

** James also opts this attitude for Katie (despite not being her brother) when a boy decides to take her out. Although he acts more like an OverprotectiveDad than an overly concerned brother. He even presents a gun-like weapon when asking him about his intentions towards Katie.

* ''VideoGame/ArtOfFighting'': Ryo enforces this where his kid sister, [[CuteBruiser Yuri]], is concerned. Both he and [[OverprotectiveDad his father]] keep a close watch on Robert and won't let him ''near her'', even though Yuri's an adult and [[LoveInterest mutually attracted to Robert.]] It was eventually {{subverted|Trope}} in Ryo and Robert's endings in ''[[https://www.youtube.com/watch?v=ARoBdaPOnNo Art of Fighting 3]]'' but, in ''VideoGame/TheKingOfFighters'' series, [[StatusQuoIsGod Robert's been pushed back to square one]].

** Seteth is rather hostile to those who show interest in his younger sister Flayn, even friendship. [[spoiler:He's actually her father, making him an OverprotectiveDad instead.]]

* In Peter Tinniswood's [[OopNorth novel]] ''Except you're A Bird'', the central character, Carter Brandon, is befriended by local hero, professional rugby player Artie Shirtcliffe. Carter is drawn deeper into the Shirtcliffe family, and the deeper he goes, the more clues appear as to something being not right. His wife Pat being in hospital, Cater develops a dangerous obsession with Artie's sister Alison. Warned off by Artie, he suspects this is because he is otherwise happily married. Eventually he discovers the awful truth: the Shirtcliffe siblings are in an incestuous relationship. After he discovers them in flagrante, there is a double suicide attempt...

%%* In the ''Fanfic/LoveLiveSunshine'' fanfic ''[[https://archiveofourown.org/works/42696828 The D in Dia stands for Death]]'', Dia Kurosawa is ''very'' protective of her little sister Ruby and wants to avoid her being taken by a heathen. This becomes a problem for Ruby as she is dating Hanamura and they worry

* In ''Series/{{Bridgerton}}'', Anthony, who is now Lord Bridgerton and in charge of his family's estate, has high standards for his sister and shoots down any man she shows interest in. He's less than pleased when Daphne and his old friend Simon, whom he knows to be a rake, start talking.

* In ''Theatre/WestSideStory'', Bernardo angrily intrudes on Tony and Maria's first meeting.
-->"Go home, ''American''. Stay away from my sister!"
** Except that the above line is directed at an enemy, not a friend, and said sister is actually ''supposed'' to be with her brother's best friend, a coupling of which said brother implicitly approves.

* During a session of ''WebVideo/OutsideXbox'' Oxventure ''[=DnD=]'' campaign, Merilwen immediately tells Prudence upon meeting her father that she is not allowed to crush on him. She is then told by Dob that all of the group, [[EvenTheGuysWantHim including the men]], are already crushing on her dad.

* In ''Anime/{{Free}}'', Rin pulls Momo away when he starts hitting on Gou/Kou.

* ''WesternAnimation/{{Arcane}}'' has a much darker version of this trope; Jinx thinks that her older sister Vi is dating Caitlyn and gets very angry and jealous as a result, since this feeds into her fear of Vi abandoning her and finding someone else as a "replacement". It gets to the point that [[spoiler:she kidnaps Caitlyn and pushes Vi to kill Caitlyn so they can "go back" to being sisters.]]

* ''WesternAnimation/{{Arcane}}'': Jinx thinks that her sister Vi is dating Caitlyn and gets very angry and jealous as a result. [[spoiler: She kidnaps Caitlyn and pushes Vi to kill Caitlyn so they could "go back" to being sisters.]]

* [[KnightTemplarBigBrother Not surprisingly]], Lelouch feels this way toward his little sister [[IllGirl Nunnally]]. It's not really so apparent in the ''Franchise/CodeGeass'' series proper, but made ''much'' clearer in the StorybookEpisode OVA ''Nunnally In Wonderland''. The only exception to this rule is [[ChildhoodFriend Suzaku]] who he is instead a ShipperWithAnAgenda about a potential relationship between him and Nunnally.

While the title says "sister," variations of it also include [[YourMom mothers]] and other female relatives (such as cousins), and for girls, the GenderFlipped "My ''Brother'' is Off-Limits." This doesn't include daughters or sons, because OverprotectiveDad and MyBelovedSmother, respectively, already covers that. Exes fall under TheBroCode instead.

This may also be a symptom of a character having a BigBrotherInstinct. Could lead to a KnightTemplarBigBrother. This trope is almost indispensable for any BrotherSisterIncest works, where it builds the initial IncestSubtext in story. Contrast BestFriendsInLaw, where the guy is all too happy for his good friend to end up with his sister. A MyBelovedSmother might have the same feelings towards her child. Unrelated to BigBrotherIsWatching. (although...)

* Completely subverted in ''Fanfic/SkyholdAcademyYearbook''.[[spoiler:Varric]] ''thinks'' that this is how [[VideoGame/DragonAgeII Hawke]] will react if she finds out that he's secretly in love with her sister. As it turns out, not only has she long since figured it out, but she couldn't be more okay with it.

* Gender-Flipped in ''Fanfic/EverydayLifeWithUltimateGirls'', with Komaru Naegi wanting to see if any of her big brother Makoto's dormmates in the girl's dorms (due to his GenderBlenderName and the fact that the intended Ultimate Lucky Student was a girl, he ended up in the girl's dorm, and the luck of [[TheJinx Nagito]] left the remaining boy's dorms in a wreck, meaning he had no choice but to stay there) are good enough to date him. Thus far, this has only played a part in [[PassionateSportsGirl Aoi Asahina's]] chapter, where the three are also accompanied by Yuta Asahina. Komaru does note her NiceGirl nature, and likes that Aoi knows about Makoto's similar personality, and even realizes that the Ultimate Swimming Pro has begun to develop a crush on Makoto.

* ''Fanfic/GuidingLightAuroraRose2081'': While in her first walk in town, one of Camilo's friends, Lorenzo, becomes quite flustered around Mirabel. Camilo promptly scares him away using Agustín's image.

* The brothers in ''Film/FoolsRushIn'' seem to be like this, at least that's what Alex fears.

* ''Film/{{Scarface 1983}}'' does this to a tragic level. Tony Montana is paranoid that his sister, Gina, would enter his criminal lifestyle. When he finds out that [[spoiler:his friend Manny Ribera had been seeing her, he shoots Manny dead without a word. Gina then reveals that the two of them had just been married]]. Gina later lampshades the somewhat Freudian motivations behind Tony's overprotective attitude towards her, [[spoiler:[[BrotherSisterIncest coming on to him]] (mockingly) just before trying to shoot him]]. The [[Film/{{Scarface 1932}} original 1932 version]] has this as well, both are a type 6.

* PlayedForLaughs in ''Series/TheBigBangTheory'': Raj tries to forbid his sister Priya from seeing Leonard, but they ignore him. Sheldon voices his disapproval of Leonard betraying a friend - [[BaitAndSwitchComment not Raj]], Howard, as Howard and Leonard previously made a verbal agreement not to go after Priya. Sheldon, however, doesn't seem to care who his own sister Missy dates. Leonard briefly convinced Sheldon to put Missy off limits, which lasted until Missy found out that Sheldon was attempting to control her sex life and [[GroinAttack expressed her disapproval]].

** In Season 3, Chandler drunkenly kisses one of Joey's sisters. Joey starts out angry but calms down when Chandler denies that he's using the sister to get over his recent break-up with Janice...only for Joey to get mad ''again'' when he learns Chandler doesn't actually know which of Joey's seven near-identical sisters he kissed.

** In another episode, Mike's friend Boner wanted to take Carol to a dance. Mike was upset at first but later accepted the pairing.

* In ''Series/{{NCIS}}'', Di Nozzo asks why [=McGee=] didn't tell him that he had a little sister and Ziva rolls her eyes. Naturally [[HandsomeLech no one would tell Tony]] that they had a little sister...

* The main ThreeAmigos of ''WesternAnimation/AvatarTheLastAirbender '' is of the brother and sister + a friend variety. Friend Aang ends up marrying the sister, Katara, but this is only ever really brought up once. In the episode “The Fortune Teller”, Aang eavesdrops in on Katara getting told she’s going to marry a powerful bender. The episode is pretty early on in the series but he’s been harboring a crush since he met her. He decides to make a move and go to the brother, Sokka, for advice because Sokka is a few years older than him. A classic OneDialogueTwoConversations ensues in which Sokka thinks that Aang is talking about one of the girls that lives in the town and Aang thinks Sokka is giving him blessing about liking Katara. Aang even asks him, “You’re okay with it?”.

* In ''LightNovel/AccelWorld'', Ash Roller isn't fond of the idea of his FriendlyRival Haru[=/=]Silver Crow getting together with his little sister Rin ([[spoiler:who, as a result of complicated circumstances, technically is Ash Roller; she had Brain Burst installed on her brother's Neurolinker]]). That said, [[spoiler:when it looks like Ash might have to be erased from Brain Burst forever to protect Rin from the ISS kit parasitizing Ash's bike]], Ash encourages Haru to be friends with his sister, so long as they're ''just'' friends.

* In ''WesternAnimation/NextAvengersHeroesOfTomorrow,'' four of the protagonists were raised together by [[Comicbook/IronMan Tony Stark]], but Francis[[note]]son of Comicbook/{{Hawkeye}} [[WordOfGod and Mockingbird]][[/note]] was not. When he explains his decision to join their team:

'''James'''[[note]]son of Comicbook/CaptainAmerica and Comicbook/BlackWidow[[/note]]: Girl?... Wait, you mean Toruun[[note]]daughter of Comicbook/{{Thor}}[[/note]]? Dude, [[LikeBrotherAndSister she's like my sister]]!\\

* In the ''Literature/HarryPotter'' fanfic [[https://jeconais.fanficauthors.net/This_Means_War/1__Surprise_Snog/ This Means War,]] Ginny's six brothers scare off her boyfriend because they've decided she's too young to date. She is ''pissed'', and decides to accelerate her plans to snag Harry so that it will be the two of them against her six brothers. Hermione, horrified, tells Ron that he is ''really'' going to regret fighting both of them at once.

[[caption-width-right:350:"And then my [[OverprotectiveDad dad]]! And then my [[MyBelovedSmother mom]]! And then my [[UpToEleven second-degree cousin]]..."]]

* In ''Manga/SpyXFamily'', Yuri zigzags this as it was by mostly his urging that Yor settle down that she looked for a [[FakeRelationship fake boyfriend]], but he becomes [[BigSisterAttraction mad with jealousy]] when he learns that Yor has been married to Loid for over a year (which is actually a lie on the couple's part).