Nana is married to her former teacher from her school days. She should have had a happy married life with the person she loves, but she doesn't get along with her husband's stepchild, Shinya, and spends her days feeling awkward. This is because Shinya was previously Nana's private tutor and they were in a romantic relationship at the time. Shinya feels irritated by Nana's distance as his stepmother, and forcibly plays with her voluptuous body. Nana accepts his twisted inferiority complex and desires as he wishes, hoping that her sacrifice will help Shinya recover...