Kei married a man with children and became a full-time housewife. Her son, Shin, witnessed his mother's infidelity in his childhood, which left him traumatized and distrustful of women. He never opened up to Kei, his stepmother. One day, when Shin secretly washed his soiled underwear in the bathroom, Kei told him, 'It's normal for a healthy boy; it's not dirty at all,' and gently wrapped her hand around his penis to wash it. Since then, to teach Shin about the wonders of the opposite sex, Kei began using her body for sex education…
