Chika Kasumi, a married woman, is being treated like a toy by her stepson, forced into degrading acts such as masturbation, blowjobs, and even compelled to accept creampie after creampie. After her husband's death, property and home rights transferred to her stepson, leaving Chika and her child with nowhere else to go. In exchange for letting them stay, she's forced to surrender her body completely. Her own biological son accidentally witnesses the humiliating scenes, leading to a volatile mix of rage, jealousy, and forbidden tension between the son and his desperate mother.