Rina to a man with a child from a previous marriage. Although she has a good relationship with her husband, she has not yet been able to open up to her introverted stepson, Haruki... At that time, her husband suggests that they go on a trip to a hot spring, and the two finally begin to grow closer. However, Haruki, who secretly harbors a desire for her, cannot resist and attacks her while she is asleep... Rina writhes violently as he forcefully caresses her, relying on his youth and vigor. The sex is a perfect match for Rina, something she has never experienced with her husband, and her body unconsciously throbs for his cock, reminding her of her past as a woman...