On the first day of the holidays, Negishi is staying at his friend Yoshio's house. Negishi is captivated by the beauty and sexy figure of Yoshio's mother Tsubasa, who greets him. That night, when Negishi goes to the bathroom before going to bed, he sees Tsubasa having phone sex with his lover. Excited by watching Tsubasa masturbate, Negishi plays with Tsubasa's heated body on the condition that he keeps it a secret from Yoshio. The young Negishi's sexual desire knows no bounds, and he even goes so far as to make Tsubasa call his lover in the middle of it all...