Futago no Haha Seihonnou / Menage A Twins

A guy named Minoru Kusonoki meets a woman on the Internet who is older than him. They get to know each other and spend an unforgettable night together. However, he can't forget that she reminds him of someone. Later, he realizes that it might be his aunt, his mother's twin sister.

After this event, Minoru begins to behave strangely. He loses control of his actions and enters into intimate relationships with various women who get in his way.