After divorcing her husband, Izumi raised her only son, Takeo. Although it was a typical 'single-parent household,' Takeo did not become rebellious and grew up healthily. One day, Takeo went on a three-week study abroad trip. Izumi left her care to her close friend Masahiko... Then an incident occurred at the Takashima residence while Takeo was away. Her supposedly divorced husband appeared before Izumi and assaulted her. Masahiko happened to be there and ended up helping Izumi...
