After losing her husband, mother Kana raised her son Teppei alone. One day, Teppei tells her he's got a girlfriend, filling her with instant joy—only for her world to shatter when she discovers BDSM gear in his room. When she asks why, she learns he's been heavily influenced by extreme adult videos and has developed a distorted understanding of sex. Determined to protect her son's future, Kana decides to personally provide him with proper sex education—using her own body. Without relying on toys or force, she gently teaches him everything with love: how to kiss, the anatomy of female genitals, and even the deeper techniques of sex, guiding him onto the right path. A special story of maternal warmth and the power of love.