Karin, the only son of mega-corporation Aizawa Group, is a college third-year who's actually an Omega. One particular day, the one who saves Karin from sudden heat is the heir and young managing director of similarly large company Totoku Group, Totoku Kyohei -- whose secondary gender is Alpha. Karin only did it with Kyohei once when he was unable to resist his heat, but later, Kyohei suddenly confesses to him......!?