Miki, a housewife, has remarried and started a new life with her son Junpei. Junpei has grown attached to her husband, to the point that they seem like blood relatives. However, perhaps because of their close relationship, her husband has started to teach Junpei extreme sexual knowledge. Worried about Junpei's future, Miki tries to give him a proper sex education in her own way, without her husband's knowledge. She teaches him how to kiss, the structure of the female genitals, and even penetration... She generously uses her voluptuous body and big breasts to teach her son about loving sex.