I have to have sex with the heir if I want to transform back into a man?! Takumi Kamisaka works at a centuries-old, well-established hot spring inn. Though the handsome heir to the inn's fortune, Mr. Moriyama, is sharp-tongued, Takumi kind of enjoys the day-in-day-out bickering. One fateful morning, Takumi wakes up to find -- he has large breasts?! When he looks in the mirror, he sees that he's turned into a beautiful woman! On top of that, Mr. Moriyama kisses him -- and in spite of himself, Takumi's whole body lights up with desire...!