History Literature / Oreimo

* CatSmile: Saori displays them from time to time.

** Kirino owns [[UsefulNotes/NintendoDS Mintendouu CS]] games, among other examples.

** The same episode has a [[UsefulNotes/PlaystationVita PS Wita]].

* LongTitle: Hence why it was shortened to [[OfficiallyShortenedTitle Oreimo.]] Lampshaded at the end of Season 2's first episode, when Ayase attempts to read the title for the next episode, only to then stop partway through and complain that the title[[note]]"The Onii-san I Trusted and Sent Off Can't Get This Hooked on Portable Bishoujo Games and Start Sexually Harassing Me"[[/note]] is way too long to fit onscreen.

* ChickMagnet: In the later novels in the series, Kyousuke has the romantic attention of [[UnluckyChildhoodFriend Manami]], [[ElegantGothicLolita Kuroneko/Ruri]], and [[{{Yandere}} Ayase]]. Hints of his younger sister possibly having more than sisterly feelings for him are also abound. He's a [[LightNovel/HarukaNogizakasSecret non-otaku reliable guy]] who doesn't mind the [[SecretKeeper otaku lifesyle of the girls]], and thus a good catch. Although he does state that Kirino has virtually turned him into an Otaku at some point, which probably further cements this trope on him given his completely normal appearance. In the (non-canon) PSP VisualNovel, he can end up with basically any of the female characters in the show.

* {{Cosplay}}: This overlaps with CosplayOtakuGirl. In the PSP VisualNovel, there's a rather risque-looking minigame version of VideoGame/{{Arkanoid}} where you basically knock off the girls' clothes as you progress. They start off cosplaying as appropriate ''LightNovel/ACertainMagicalIndex'' characters (for instance, Kirino as Mikoto and Kuroneko as Index) and Index herself guest stars. They end up in bikinis [[FanService for some reason]].

* WrongGenreSavvy: Kyosuke finds the implications of his little sister playing H-Games about little sisters ''disturbing''. To his peace of mind, Kirino makes clear that she can tell [[ThisIsReality 3D reality]] from [[{{Hentai}} 2D fiction]] fine, and her obsession with them comes from the over-the-top {{Moe}}ness of the characters in an extreme case of PeripheryDemographic. However, in a later (anime-only) episode it's still implied extremely strongly that she enjoys the H-scenes [[ADateWithRosiePalms exactly as they are meant to be enjoyed]]...

The author, Tsukasa Fushimi, and Creator/KazumaKamachi have co-written a crossover web series between this and ''LightNovel/ACertainMagicalIndex'' called ''Ore no Imouto to Railgun Collaboration Project!''

* EntertainmentAboveTheirAge: Kirino, a teenager, loves to play little sister-themed [[HGame H-games]].
* {{Expy}}:
** Kyousuke's narration style is strongly reminiscent of [[LightNovel/HaruhiSuzumiya Kyon's]], without the erudite asides.
** That, or (at least in the anime) ''VisualNovel/{{Clannad}}'''s Okazaki, what with the whole constant sarcasm, genuinely trying to help people and having the same seiyuu.
** During episode 14, as Kyosuke play tests Kuroneko's video game, one can spot a character on the computer screen that bears a suspicious resemblance to Kyosuke.
** Episode 2 of season 2 features an Ayase expy.

** The after story, written by the author of the light novels, effectively confirms that [[spoiler:[[TheyDo Kyousuke and Kirino are indeed still together]]. They only ended the public side of their relationship as the ending seemed to hint, but continue in private rather successfully it appears.]]