After losing her husband, Reika has been living with her son Naoto. However, when Naoto becomes an adult, she decides to remarry and start a new life. Meanwhile, Naoto is unable to accept his mother's sudden remarriage and rebels on his own... One day, Naoto accidentally witnesses his mother being creampied by his new father. Naoto holds his breath at the sight of Reika's ecstatic expression, but he has no idea at the time. Reika is obsessed with the allure of creampies...