Kono Naka ni Hitori, Imōto ga Iru!

Nakaimo - My Sister is Among Them!
Cover of the first light novel
この中に１人、妹がいる！ (Kono Naka ni Hitori, Imouto ga Iru!)
Genre	Romantic comedy, Harem Mystery
Light novel
Written by	Hajime Taguchi
Illustrated by	CUTEG
Published by	Media Factory
Demographic	Male
Original run	August 25, 2010 – March 25, 2013
Volumes	10
Manga
Kono Naka ni Hitori, Imouto ga Iru! - Who is "IMOUTO"?
Illustrated by	Mottun*
Published by	Media Factory
Demographic	Seinen
Magazine	Comic Alive
Original run	April 2011 – December 2013
Volumes	5
Anime television series
Nakaimo – My Sister is Among Them!
Directed by	Munenori Nawa
Written by	Go Zappa
Music by	Hikaru Nanase
Studio	Studio Gokumi
Licensed by	NA Sentai Filmworks
Original network	TBS, MBS, CBC, BS-TBS
Original run	July 6, 2012 – September 28, 2012
Episodes	12 + OVA (List of episodes)

Nakaimo - My Sister is Among Them! (この中に１人、妹がいる！, Kono Naka ni Hitori, Imouto ga Iru!^?) is a Japanese light novel series by Hajime Taguchi. It was adapted into an anime television series by Studio Gokumi. The anime was aired between July 6 and September 28, 2012. The anime series is licensed by Sentai Filmworks and is streaming on Crunchyroll and Anime Network.

The Mikadono Group (帝野グループ, Mikadono Gurūpu^?) is a worldwide business company based in Japan and led by Kumagoro Mikadono. He names his son Shogo heir to his position in the company. However, after Kumagoro dies, his widow Kanoko becomes the new acting chairman as Shogo transfers to his father's alma mater Miryuin Private Academy. According to his father's will, Shogo will take over the company after he graduates provided that he finds a life partner before then. Fortunately, there is a large female population at Miryuin Academy to choose from. Life at the Academy will not be all smooth sailing, however. He is immediately popular because of his name and position as heir to Kumagoro's company and has caught the eye of several female students. To complicate matters further, although he was raised as an only child, Shogo apparently has a younger half-sister who was raised separately who also goes to the school and intends to get closer to him without revealing her true identity. How will he act knowing that any girl he chooses to be his life partner may also be his sister?

Nakaimo - My Sister Is Among Them!, was adapted into a twelve episode anime with a special OVA episode. In April, 2012 it was announced that Studio Gokumi would be adapting the light novel series into an anime for an airing sometime in June. Between April 5, and June 28 promotional ads were streamed announcing the anime's start date to be July 6, 2012 by TBS. In September 2012 Japanese production company Media factory released the entire series on DVD and Blu-ray, a special unaired OVA entitled "Brother, Sister, Lover" was bundled with the release. In addition to the OVA, bonus material included footage from a special event that took place on July 16. The Blu-ray's jacket also features cover art done by the illustrator of the light novel series.