One year into her marriage, Aria lives happily with her husband, Noboru. One day, an older man moves in next door, wearing a shabby suit. Aria is momentarily stunned when she sees him—it's Kaiho, her former boss from the company where she used to work before marriage. He had been fired from his job and abandoned by his family. Consumed by jealousy over Aria's happy life, he snaps, "How dare you sit there so innocently as a housewife..." From that day on, he begins relentlessly tormenting her daily life.