Miki was living a married life with her husband Kanichi when her father-in-law, Kan, moved in to recover from an illness. Kan, who had long been attracted to Miki, began raping her during the day while her husband was at work. Unable to tell her husband, Miki was forced to continue obeying Kan's demands. The acts grew increasingly extreme, pulling Miki deeper into an abnormal and humiliating situation.