Kana is a married caseworker who supports troubled residents. She is assigned to Yoshino, a man devastated by the death of his longtime dog Belle, but he irrationally blames Kana for the animal's death. After she is removed from his case, the enraged Yoshino ambushes her on her way home from work, locks her inside Belle's old cage, and subjects her to captivity, rape, and creampies as his replacement pet.