is a Japanese light novel series written by Tsukasa Fushimi, with illustrations provided by Hiro Kanzaki. The series includes 14 novels released from August 2008 to June 2020. A manga adaptation drawn by Sakura Ikeda was serialized in ASCII Media Works' Dengeki G's Magazine between 2009 and 2011. AIC produced a 12-episode anime adaptation in 2010, with four additional episodes streamed online in 2011. A-1 Pictures produced a 13-episode second anime season in 2013, with three more episodes streamed online later that year. Bandai Namco Games developed three visual novelvideo games from 2011 to 2013 for the PlayStation Portable and PlayStation 3 consoles.
Plot
Kyosuke Kosaka, a normal 17-year-old high school student living in Chiba, has not gotten along with his younger sister Kirino in years. For longer than he can remember, Kirino has ignored his comings and goings and looked at him with spurning eyes. It seemed as if the relationship between Kyosuke and his sister, now fourteen, would continue this way forever. One day however, Kyosuke finds a DVD case of a magical girl anime which had fallen in his house's entranceway. To Kyosuke's surprise, he finds a hidden eroge inside the case and he soon learns that both the DVD and the game belong to Kirino. That night, Kirino brings Kyosuke to her room and reveals herself to be an otaku with an extensive collection of moe anime and younger sister-themed eroge she has been collecting in secret. Kyosuke quickly becomes Kirino's confidant for her secret hobby. The series then follows Kyosuke's efforts to help his sister to reconcile her personal life with her secret hobbies, while restoring their broken relationship and coming to terms with their true feelings for each other.
Characters
Main
; ;
Supporting
Media
Light novels
Oreimo began as a light novel series written by Tsukasa Fushimi, with illustrations provided by Hiro Kanzaki. ASCII Media Works published 12 novels under their Dengeki Bunkoimprint between August 10, 2008 and June 7, 2013. The first volume of a two-part alternative ending of the series subtitled Ayase if was released on August 10, 2019, and the second volume was released on June 10, 2020.
Manga
A manga adaptation based on the light novels drawn by Sakura Ikeda was serialized in ASCII Media Works' Dengeki G's Magazine between the March 2009 and May 2011 issues. Four tankōbon volumes were released under ASCII Media Works' Dengeki Comics imprint between October 27, 2009 and April 27, 2011. The third volume was released in regular and special editions; the special edition came bundled with an Ayase Aragaki figurine. The manga has been licensed in North America by Dark Horse Comics. A follow-up manga, Ore no Kōhai ga Konna ni Kawaii Wake ga Nai, began serialization in the July 2011 issue of Dengeki G's Magazine and features Ruri Goko as the main heroine. The manga ended serialization in the magazine's May 2014 issue and continued serialization in Dengeki G's Comic between the June 2014 and July 2015 issues. The first volume was released on May 26, 2012, in regular and special editions; the special edition came bundled with a Kuroneko figurine. Six tankōbon volumes were released under ASCII Media Works' Dengeki Comics imprint between May 26, 2012 and July 27, 2015.
Drama CD and radio shows
A drama CD, based on events from the first and third volumes of the novels as well as a newly written scenario by Tsukasa Fushimi, was released by ASCII Media Works on March 31, 2010. The CD stars Ayana Taketatsu as Kirino and Yūichi Nakamura as Kyōsuke. An Internet radio show titled Ore no Imōto ga Konna ni Kawaii Wake ga Nai to promote the anime adaptation streamed 24 episodes between August 13, 2010 and July 22, 2011 via the official website of the anime. The show was hosted by Taketatsu, who plays Kirino in the anime, and Kana Hanazawa, who plays Kuroneko. A second Internet radio show to promote the second season of the anime started on April 11, 2013. The show was again hosted by Taketatsu and Hanazawa. Even though the show was limited to the Japanese speaking audience, the e-mails and comments from fans outside Japan were also accepted and sometimes read during the show, and the official website of the show has been translated into English.
Anime
A 12-episode anime adaptation produced by AIC, directed by Hiroyuki Kanbe, and with screenplay by Hideyuki Kurata aired in Japan between October 3 and December 19, 2010. The series was released over eight BD/DVD compilation volumes, each holding two episodes, between December 22, 2010 and July 27, 2011. Four original net animation episodes were streamed through the official website, as well as several other websites such as Nico Nico Douga, Showtime Japan, and MovieGate, which began on February 22, 2011. The first two were released on June 27, 2011, together with the seventh BD/DVD volume and the last two were released on July 27, 2011, together with the eighth. These episodes feature a break in the original story arc starting at episode 12 and offer an alternate ending from the TV broadcast. The anime retains the voice cast from the drama CD. The opening theme for the anime is "Irony" by ClariS and is composed by Kz of Livetune, while each episode features a different ending theme sung by one of the voice actors. The music of the anime is composed by Satoru Kōsaki and a soundtrack was released on January 12, 2011. Aniplex of America began streaming and simulcasting the series in North America through Anime News Network, but security issues involving the illegal leaking of episode two online resulted in the stream being placed on hold. The stream of Oreimo returned to ANN with the first four episodes on November 8, 2010. Aniplex of America released the series on an English-subtitled DVD box set in October 2011. The anime is licensed by MVM Films in the United Kingdom. A second 13-episode anime season, titled Ore no Imōto ga Konna ni Kawaii Wake ga Nai. and produced by A-1 Pictures, aired between April 7 and June 30, 2013 and was simulcast by Crunchyroll. An additional three episodes were screened at Otakon 2013 on August 9, 2013, and then streamed worldwide on August 18. The episodes were simulcast by Crunchyroll at the same time as the Japanese broadcast and were available until August 31, 2013. Despite the change in animation studio from the first season, the second season has the same staff as the first. The opening theme is "Reunion" by ClariS, while a contest was held for the second season's ending themes. This series has also been licensed by Aniplex of America. A-1 Pictures collaborated with Chiba Urban Monorail to promote the second season by making an Oreimo-themed monorail train, which remained in operation until September 30, 2013. In addition to decorating the exterior of the train, the anime characters were featured in in-train advertising to provide passengers with helpful tips about local sightseeing facilities and shops. In addition to their own series, the characters from Oreimo also make cameo appearances in the episodes of the anime adaptation of Eromanga Sensei, another light novel series written by Fushimi and illustrated by Kanzaki.
Video games
A PlayStation Portable visual novel titled Ore no Imōto ga Konna ni Kawaii Wake ga Nai Portable was developed by Bandai Namco Games and released on January 27, 2011. The limited edition bundle included an OAD, a sister-talk bonus CD, and an additional game for the PSP. A fighting game titled Shin Imōto Taisen Siscalypse, based on the fictional game in the series, was released by Kadokawa Contents Gate on the Yahoo! MobaGe Service on January 20, 2011. A second PSP title, Ore no Imōto ga Konna ni Kawaii Wake ga Nai Portable ga Tsuzuku Wake ga Nai, was released on May 17, 2012. The opening theme of the second PSP game is "Nexus" by ClariS. A PlayStation 3 game, Ore no Imōto ga Konna ni Kawaii Wake ga Nai Happy End, was released on September 26, 2013 in Japan. Kirino also makes a cameo appearance in the A Certain Magical Index PSP game, being another game based on a light novel series published by ASCII Media Works. Kirino also appears as a playable character in , with Kuroneko as a supporting character.
Reception
The Mainichi Shimbun reported that the fourth volume sold the most copies of any light novel in August 2009. Anime News Network reported in April 2012 that the first nine light novels had collectively sold 3.7 million copies in Japan. ANN writer Kim Morrissy cited Oreimo as the series that revived the little sister boom, and made comparisons to Tsukasa Fushimi's later series Eromanga Sensei. Morrissy stated that the key difference between the two, despite sharing a little sister moe theme, is that Oreimo has committed the ultimate incest taboo due to Kyosuke and Kirino being related by blood, whereas the siblings in Eromanga Sensei lack a blood relation, hence "allowing the romance to play out with a less direct connection to real-life incest".
