Teacher Mari one day, along with her husband and fellow teacher Tetsugaku, visited the home of Yuugo, a student in their class who was refusing to go to school. Although the school had given up on Yuugo due to his problematic behavior, Mari insisted on making a home visit. However, Yuugo made Mari and Tetsugaku drink tea laced with sleeping pills and then raped Mari in front of Tetsugaku. During the act, Yuugo's father Satoshi, a yakuza, and his henchmen appeared and the three of them gang-raped Mari.
