With her husband's retirement approaching, Seiko, a mother, does laundry on the balcony to save money. However, recently her husband has started to focus on his work and comes home late every day... Her son Wataru, who had heard his mother masturbating in the bathroom using toys out of loneliness, begins washing the laundry in front of him on another day using bath water, and his lust explodes at the sight of his mother's wet nipples and the dripping Shizuku. "I'll do it for you, Dad!"