Yukari and her husband moved in with her father-in-law due to his job transfer. One day, while cleaning, she discovers SM paraphernalia like ropes and candles in his belongings. Her father-in-law notices her discovery and, seeing her reaction, realizes she's harboring a growing desire. "Don't be afraid, you seem quite interested," he says, slowly approaching and tying her up. Despite her fear, Yukari experiences pleasure...