Rei and Taishi haven't had sex since they got married. They've been married for four years and have no children. One day, when his wife comes home in the morning for the first time, Taishi hires a detective agency to look into Rei's background. The investigation reports that she is having an affair with an ex-boyfriend from her school days. Taishi roughly embraces Rei, who has just come home in the morning, and while scooping out the other man's sperm, tries to overwrite it with his own, but...