Keisuke, a son, has fallen in love with his mother Yuka. She has a beautiful, ripe body. Whenever she exudes her defenseless sex appeal, he starts thinking of her not as a mother but as a sexual object. Unable to resist, he plots to make her his own, sneaking around when his father isn't looking and pounces on Yuka. "Do you like the chastity belt I gave you as a present? If you want me to take it off, you can do so." Keisuke uses the chastity belt to control his sexual desire and take control of Yuka's body. Yuka is confused by Keisuke's outrageous actions, but she resists him...