Onii-chan Dakedo Ai Sae Areba Kankei Nai yo ne

Onii-chan dakedo Ai sae Areba Kankeinai yo ne! (お兄ちゃんだけど愛さえあれば関係ないよねっ; lit. "As Long as There's Love, It Doesn't Matter If He is My Brother, Right"), or Oniai for short, is a Japanese light novel series written by Daisuke Suzuki, with illustrations by Gekka Urū. The series is published by Media Factory under their MF Bunko J imprint starting in December 2010, with six volumes released as of May 2012. A manga series by Kurō Rokushō began serialization in the December 2011 issue of Media Factory's seinen manga magazine Monthly Comic Alive. An anime adaptation by Silver Link began airing in Japan in October 2012. The anime has been licensed for streaming by Funimation Entertainment, premiering Friday October 12 at 12:30 pm.

Plot
Himenokouji twins Akito and Akiko have finally reunited with each other after separation due to the death of their parents. After six years of living apart they suddenly began to live under the same roof due to Akito's desire to live as a family unit once more. Things were fine at first until Akiko began to express her incestuous love for her older brother, who only sees her as a little sister.

Official

 * Media Factory
 * Anime's Official Website

Other Sources

 * Oniai
 * Light novel
 * Anime