Onii-chan Dakedo Ai Sae Areba Kankei Nai yo ne

After the death of their parents, Akito Himenokouji and his younger twin sister Akiko were adopted by separate families. Six years later, they now live on their own, under the same roof. Akiko makes no effort to hide her brother complex. She even goes as far as trying to convince her brother to make their first night together a memorable one, to no avail. Akito calmly rejects his sister's many advances and deems loving his blood-related sister impossible. However, Akiko is determined to prove that love can overcome any obstacle.

The story is about the Himenokouji twins named Akito and Akiko who got separated due to certain circumstances and after years of living apart they suddenly began to live under the same roof once again. Things were fine at first until Akiko began expressing her love for her older brother. Now Akiko must fight to defend her extraordinary love for her Onii-chan as she battles against all odds and three other girls who are after her beloved Onii-chan.