Kana, a mother who has been raising her son Teppei on her own since losing her husband. One day, Teppei tells her that he has a new girlfriend, and Kana is happy for a moment, but then she discovers some SM goods in Teppei's room. When she asks him why, she learns that he was influenced by extreme adult videos. In order to prevent her son from learning any more incorrect sexual knowledge, Kana begins to use her own body to teach her son sex education. Sex with love that does not rely on force or tools...A beautiful mother intimately teaches him everything from how to kiss to the structure of the female genitals and the Iroha of sex.