When Yukari's husband is transferred, she and her husband move in with her father-in-law. One day, while cleaning, she finds some SM paraphernalia, such as ropes and candles, in her father-in-law's belongings. Her father-in-law notices this, but when he sees Yukari's reaction, he realizes that she is becoming sexually frustrated. "There's no need to be scared. It's not that you're not interested, is it?" he says, slowly approaching Yukari and tying her up. Yukari is frightened, but she feels pleasure...