I [M] saw my girlfriend [F] cheat and loved it

My gf and me were at a house party of her colleague. After midnight all of them left except both of us and him. We were drinking and they were flirting. I could cut the sexual tension with a knife. After a while they went on the balcony for a smoke and I pretended to pass-out. They were sitting on the opposite couch and talking, when he made a move and was caressing her knee, and then kissed her. She was taken aback looked at me. I was pretending to be passed out and she started making out with him. After some heavy makeout she stopped and she went to get a refill in the kitchen. He followed. I knew this was it. After a couple of minutes I got up and peeked into the kitchen..he was getting all touchy and kissed her neck from behind and she was half reluctant, and said but my bf is here. Her eyes closed her head on his shoulder..he slowly unbottened her blouse. And kept teasing her.she gave in and kissed him he picked her and put her on the kitchen table. Put his hand under her skirt pulled down her panties pulled out his hard cock and fucked her good. I was so turned on..after they were done I went back to pretend sleep. She came back to the living room woke me up. I pretended to slur and she got a cab and we left. Once home I fucked her like a man possessed and didn’t tell her I knew.

Source: reddit.com/r/gonewildstories/comments/kdje4r/i_m_saw_my_girlfriend_f_cheat_and_loved_it