Kousuke just transferred into rural Harusaki Gakuen, but the school accidentally didn’t reserve a room for him. After much searching he found a free room, but it’s at a girls’ dorm! Thus begins his double life: as a boy at school and as a girl named Mae in the dorm. A pretty common scenario, and one in which his cover is bound to be blown eventually. However, he has his imouto Runa on his side, who followed him to the dorm so that no other girl can take her oniichan away. Also, the most ojousama-like chara in the school is actually a trap.