OniAi is a tV series anime that premiered in fall 2012, produced by SILVER LINK..

About the production: the story comes from a light novel, there are 12 episodes of about 24 minutes and its current status is "finished".

Its main genres are comedy, ecchi and romance, with themes such as Kuudere, Female Harem, Incest and School.

On AniList, OniAi has an average score of 60%, an average score, and appears on 72,976 users' lists.

Akiko is thrilled to be reuniting with Akito, the handsome older brother she hasn’t seen in years! In fact, she might be a little too excited. This pint-sized cutie has a big brother complex, and she’s not interested in sharing his attention. Unfortunately for little sister, she and Akito won’t be living alone: three gorgeous girls from the student council will be along for the ride! (Source: Crunchyroll)

Official synopsis from AniList.