According to character and anime hobby shop Amiami, it has revealed that ecchi/romance anime series Kono Naka ni Hitori, Imouto ga Iru! will be getting an original video anime.

OVA will be the unaired 13th episode of the series titled “Big Brother, Little Sister, Lover” and it is set to release in Blu-ray Disc on March 27, 2013.

Shōgo Mikadono is the son of an industrial magnate named Kumagorō Mikadono who passed away. As a final wish, Kumagorō imposed a condition Shōgo must meet before he can inherit the family legacy—find a female mate at school. Shōgo transfers into a school to fulfill that condition. However, he learns that he has a younger sister from whom he was separated at birth. He does not know what his long-lost sister looks like, but she happens to be one of the students at his new school. [MAL]