Toru is a veteran erotic writer who feels his father-in-law's gaze entangled in his heart. After losing his wife, his creative drive has waned, but his son's wife, Ran, who has started living with him, is quietly supporting the household. Her sweat-soaked housework, her modest smile - Toru knows he shouldn't look, but he can't help but be captivated by Ran's young beauty, and his heart races. When they are alone in the evening, the desire that he had buried deep in his heart begins to faintly light up. The urge that he thought he had suppressed quietly awakens, as if guided by Ran's moist mouth...