A busy stepmother Akari finds her stepson Kazuma locked away due to being heartbroken by a girl. She accidentally catches him masturbating and becomes aroused while fantasizing about having sex with him. Learning that his isolation stems from being rejected by a woman, she decides to help him overcome his fear of females by touching his body. As they become closer, Akari begins to see Kazuma differently and eventually allows him to penetrate her. They share an intense sexual relationship filled with passionate lovemaking sessions that blur the lines between family members...
