It's been three months since she got married. Although she has a good relationship with her husband, her relationship with her stepchild, Takayuki, who is a student retaking the entrance exams, is a little complicated. One day, Yasuko witnesses Takayuki sleeping with his penis exposed, and cannot hide her excitement. Her long-awaited, lust-filled body is unable to resist her sexual desire, and she involuntarily plays with his erect penis... Takayuki ejaculates right away, but his sexually ravenous penis is not satisfied with just one ejaculation, and he shows off his rock-hard cock to her again...