Satomi, a mother of two, realizes that Masakazu is completely indifferent to women when her son, Masakazu, and daughter, Eriko, are arguing with each other. She is at a loss, and Satomi politely explains what her gender is, but Masakazu doesn't show her interest. Realizing that she can't convey it in her words, Satomi gives her sex education with her own body...
