Riko's only son, Yuji, is a timid boy who is always bullied by his friends. Worried about her son, Riko warns his friends and tries to put an end to the bullying, but... she falls into the trap of a precocious brat who pretends to be spoiled and aims for her mother's big breasts. She thinks he's just a child and underestimates him, but before she knows it, she's been satisfying the sexual needs of children every day...