"Let's swap partners..." When Manami hears this request from her trusted boyfriend, she receives a cruel shock. However, not wanting to lose his affections, she gives her body to a man she's never met or even seen before. The one who notices that the unwanted connection is breaking Manami's heart is not her callous boyfriend, it's her swinging partner, Tadano. Tadano has one tryst after the other with Manami at the whim of his selfish girlfriend. When he sees how hurt Manami is, he tries to comfort her with kindness. The time they spend together starts to become very important to Manami. Even though she knows he is someone else's lover, she starts to fall in love with him...from Renta!