Shindo Shou, a freshman at the ordinary boys' school, Yosei High School, has just started his dream dorm life. One day after school, when he returns to his room, he finds a stranger elementary school student and a kindergartener there…! By order of the chairman, he is forced to live with them for a year…!? A coming-of-age story under one dorm roof.

At dusk, in front of recluse Tanner King's mansion, Ivy stands determined. Tanner is her enemy and this is the first step in her plan-she'll befriend him, insinuate herself into his life as his housekeeper and then execute her mission. But when the door opens and Tanner stands before her, he takes her breath away. Suddenly Ivy's mission doesn't seem nearly so straightforward!