江ノ木 勇作

The protagonist. He's a college boy who lives alone. He's very smart and can easily teach others. After becoming Miina's boyfriend the two begin living together with the permission of Miina's mother because Miina is too young for him to marry. They must keep their relationship a secret though her close friends already know.

He is best friends of Kentarou and attends an English club at his college.