When Yuma’s mother remarries, his teacher Mr. Ayato Hinohara becomes his new stepbrother! And, it turns out Ayato is a wolf in sheep’s clothing; when midnight comes around, his personality does a 180! Ayato sticks objects into Yuma’s backside, tells Yuma to bring a girl for him to play with… this guy is out of control! At first, Yuma’s confused by Ayato’s dark side, but his body… slowly adjusts to him… Just what kind of relationship is in store for them!? A naughty story about an unlikely pair living under the same roof!