Yuko Yajima was forced into remarriage while burdened with her family's debt. Her husband, Katsuhiko, rules the household like a tyrant, mistreating both his son Makoto and Yuko, regularly assaulting her when drunk. Unbeknownst to them, Makoto secretly observes his parents' turbulent relationship. One day, returning home from cram school, Makoto notices an unfamiliar man's shoes in the hallway. Emotions begin to stir between stepmother and stepson—until an unexpected incident threatens to change everything.