Unable to bear her husband's domestic violence and infidelity, Eriko runs away to her younger sister's house. Her sister's husband, Taichi, greets her instead as her sister can't come home today because she has to work. After dinner, Taichi invites her out for a drink to cheer her up. After a while, Eriko seems to get drunk and starts laughing brightly, so Taichi feels relieved, but when the drinking party ends and Taichi goes to the bath, an incident is waiting for him. "I'll wash your back for you," says Eriko, who actually becomes naughty when drunk, as she comes in naked. Taichi panics and Eriko's hand reaches for his crotch...