Six months ago, Kaoru remarried a man with a child, becoming the new stepmother to his teenage son, Atsushi. Concerned that Atsushi spends all his time locked in his room playing video games, Kaoru wishes for him to gain more life experience. One afternoon, while her husband is away, Kaoru casually asks Atsushi, "You're still a virgin, aren't you?" Taken aback by the sudden question, Atsushi soon finds himself losing his virginity to his stepmother. What follows is an unbelievably pleasurable deflowering—a fantasy come true that every man envies.