After work, I made an appointment with my girlfriend to have sex because we haven't done it all week. As soon as I got home, I was greeted by the sight of Sakura, my girlfriend, kneeling on the floor, revealing her sexy panties and inviting buttocks. Without hesitation, I rushed over and quickly inserted my manhood inside her until her moans filled the room, only then did I realize it wasn't Sakura but her older sister. Angry at her husband, the older sister had come to her younger sister's house that day to confide, and coincidentally, she was dressed exactly like Sakura and had a similar figure, so I mistook her and engaged in intimate activities with her. The next day, I made the same mistake again thinking she had left, and this time it seemed to trigger the deep-seated sexual desire within her, as she actively entered the room to beg me to continue pleasuring her while her younger sister was out. Thus, their illicit affair continued to happen regularly, more frequently behind the back of the innocent and pitiful younger sister.