Pure Mail by Overflow (Jap) - Adult Sex Game

Kei has a difficult past with an abusive father and has problems socializing with people directly, so he chooses chatroom acquaintances over real people. But one day he discovers that his chat partner EVE is his classmate Midori, who has a crush on A,W - his internet alias. He falls in love with Midori but hides his idealized A,W identity from her so she would not be deterred by his real self, tainted by past and present events, and blackmailed into a slave-like relationship with the school's web mistress.