Yuuki lives alone with his mother Yoshino (Yoshino Hanaoka). Six years after his father's passing, Yuuki has been relying on his aunt, Maki (Maki Hojo), for care. Their close bond gradually develops into romantic feelings. One day, Maki catches Yuuki masturbating and, unable to restrain himself, he suddenly forces himself on her. However, the act is witnessed by his mother Yoshino. How the relationship between the three will evolve is now the focus of attention.