Futagami double manga

Futagami Double summary:

Futagami Sousuke, 14 years old, is a normal student, wishing to live a normal life. But everything changes the day he sees a doppelganger of himself in his house. Since then, the girl he has a crush on, Amane, will introduce him to another side of his world he had no idea about, and there won't be anymore of the dear peaceful days for Futagami.