I went to hang out at my girlfriend's best friend's place. My old classmate, now her best friend, had grown into a sexy figure with thick, voluptuous big tits and a huge ass. While my girlfriend was distracted by accidental panty shots, she seemed aware of what was happening. When she stepped out, I made a move on the best friend. She acted surprised at first, but her body didn't resist at all. As we kissed and embraced, her boyfriend suddenly returned home and caught us. That's when I learned he'd already slept with my girlfriend. With the couples officially swapped, chaotic, messy sex unfolded right in front of my girlfriend and the best friend's boyfriend—I kept thrusting my cock inside while sucking his dick. In the middle of it all, the best friend lost control and peed herself in a shocking, massive accident.