Staying over at his friend's house, Yutaka accidentally catches his friend's older sister Aki right after her bath, her lush naked body instantly captivating him. His heart races, his cock hardening with arousal. Seeing his reaction, Aki—still reeling from her recent separation with her husband and overwhelmed by pent-up desire—gleefully reaches down and begins touching Yutaka's crotch. Though still a virgin, Yutaka gives in to her advances and satisfies her, but the intense pleasure awakens something in him. Unsatisfied and craving more, he soon takes the next step himself.