Boku wa Mari no Naka FC

The manga follows the story of Mari Yoshizaki, an "angel-like" beautiful high school girl with a certain secret she has been hiding from everyone, and Isao Komori, an idle hikikomori (one who adnormally avoids social contact) young man; the highlight of his day is seeing Mari at the convenience store. The story begins as Isao wakes up in his room, but something feel amiss about the room and even his own body.