While staying over at my girlfriend's house during her father's absence, her older sister came back home completely drunk and mistook me for her boyfriend! Even though she realized the mistake halfway through, she couldn't care less and started playing with my cock anyway—what a gorgeous, seductive woman. Things quickly escalated, and before I knew it, she was seducing me with her big tits and letting me creampie her. I truly care about my girlfriend, but when faced with such an aggressive older sister, I just can't hold back. Even with my girlfriend right there nearby, the raw sensation felt so incredible that I couldn't stop thrusting inside her!