Jiro, the younger brother who lives with his brother and his wife. Her sister-in-law, Mami, used to be her Jiro's tutor, and since then Jiro has been fond of Mami. One day, Jiro, who was being taught by Mami, ends up watching. Where his brother and Mami are having sex... Then the two got married. Jiro can't accept that the woman she liked has married her brother, so he pushes Mami down to make it his own. However, Jiro started filming Mami, who still resisted, with a video camera.
