Miyashita Reina, the stepdaughter he had raised with great care. When he found out that she was indulging in lewd sex with her boyfriend, something inside her broke. He thoroughly investigated her erogenous zones and decided to plunge her into a hell of pleasure for seven days. Her innocent mask was torn off by her stepfather's relentless caresses, and he imprinted on her a pleasure that was even greater than that of her boyfriend. She climaxed multiple times every day, and over the course of seven days, her reason crumbled. This is the record of the immoral upbringing that transformed this cute stepdaughter into a female, loyal to pleasure.