After her mother's death, Risa notices strange changes in her stepfather. Claiming "I'm taking your mother's place," he handcuffs her, ties her up with rope, and torments her with a vibrator. His violent behavior worsens each day, forcing her to care for her step-grandfather while wearing a vibrating device. To escape her stepfather, Risa surrenders herself to a forbidden relationship with her step-grandfather, the only person who understands her. Caught between love and hatred, she gradually moves toward a new destiny.