The neighbor of the apartment where Mei spends happy days with her engaged boyfriend was a metamorphosis who masturbates while eavesdropping on Mei's exchanges through the wall. Mei is a little sloppy, as if you inadvertently wear your boyfriend's shirt as if it were yours. The neighbor Saeyama, who noticed there, sent the luggage on purpose and threatened to take responsibility for Mei who used it without permission. Mei, who felt unsatisfied at night with her boyfriend, felt pleasure in Saeyama's forcible sex.