The son harbors deep resentment toward Yuki, his father's new wife, venting his grief over losing his real mother onto her. Yuki gradually begins to feel pleasure from the son's abuse and torment, eventually losing control over her desires. One day, the son notices the stain on the panties Yuki wore during one of his abuses and realizes she has been aroused. Discovering this, he berates her as a "slut with no sense of chastity" and starts sexually dominating her—forcing a vibrator inside her and making her crawl like a dog—beginning her complete domestication.