Kazuo, who does not get along with his father, secretly loves his beautiful mother, Yumi. One day, when his father comes home drunk as usual and Yumi busily looks after him, Kazuo is unable to bear it any longer and pours out all his desires on her body. Yumi is afraid that their forbidden relationship will be exposed, but she cannot escape the pleasure. The two of them keep their affair secret from their father and before they know it, they are obsessed with mother-son incest.