Yuki returns to his hometown after years in Tokyo, a place of bittersweet memories, especially of his sister-in-law, Shizuka. As kids, they were inseparable; being an only child, she treated him like a brother, which delighted her but frustrated Yuki—he wanted to be her man, not her brother! She fell for his older brother and married him. To forget her, Yuki fled to Tokyo. Returning, memories flood back. Shizuka, more beautiful than ever, and her husband warmly welcome him. That night, fetching water, Yuki overhears Shizuka wanting sex with his brother, who refuses, letting Yuki witness her masturbating. Knowing she’s unfulfilled, Yuki’s desire to claim her surges. Next morning, with his brother at work, he ravishes her! Shizuka knows his feelings but loves her husband, who loves her. Yet, she can’t deny Yuki’s affection. During his stay, they secretly fuck. At departure, Shizuka asks when he’ll return, but Yuki knows he’d disrupt her happiness. To truly forget her, he vows never to return...