On the day I returned with my wife to her family home, I unexpectedly found her older sister and her husband were also visiting. Her sister was even more elegant and beautiful than my wife, and I couldn't help but be drawn to her, stealing glances each day. Soon, I began fantasizing about doing all sorts of things with her. Then one day, she suddenly made a move on me. Despite being my sister-in-law, she wanted to seduce me right under my wife's nose, excited by the thrill of stealing her own brother-in-law. Though not blood-related, it felt emotionally like incest. Unable to resist, I gave in to her advances—and found myself completely aroused by her.