Jiro, the younger brother, lives with his older brother and his wife. His older brother's wife, Mami, used to be Jiro's private tutor, and Jiro had a crush on Mami ever since. One day, while being tutored by Mami, Jiro sees his brother and Mami having sex... And then the two get married. Jiro can't accept that the woman he loved has married his brother, so he pushes Mami down to make her his own. However, Mami still resists, so Jiro starts filming her on his video camera...