My girlfriend sleeps over at my friend's house.

The last fine weekend my girlfriend went to dance and found Gero, a friend of mine with whom they had gotten along well. I couldn't go because I was going to take a partial exam the next day and had to sleep early. Around 4 am my girlfriend wanted to leave but I wasn't answering because I had already fallen asleep. Gero told her she could wait for me at his house or stay overnight if she wanted. My girlfriend accepted and they left in his car... When they arrived, they started chatting with beers and music. In a while, my friend tells him that there was a cutie at the club who had screwed him all night and left him hot. He mentioned it several times but my girlfriend didn't say anything. They kept talking until Gero said he was going to change for bed and went to his room. My girlfriend tried calling me again but I was still asleep. A while later, Gero came out without a shirt with just a soccer short on and no boxers. His cock was showing below the short but my girlfriend pretended not to notice. They kept talking and he said again I'm leaving this cutie, she's a slut mom. My girlfriend laughed and said well, I'll have to suck her off so you can come and leave me alone? haha. They both laughed and kept drinking. At one point, Gero got up and sat next to her. His cock was really showing now. And after they'd had enough, he said he needed to come or he wouldn't be able to sleep. My girlfriend who was already pretty drunk told him not to go, and Gero said relax, I won't fuck you, then my girlfriend just stayed quiet. Then the guy took off his soccer short and she just sat there staring at his cock. Gero seeing that she wasn't saying anything grabbed her neck and brought her head down... my girlfriend didn't say anything and he started screwing her slowly until she stopped him and said you told me we weren't going to... fuck. The son of a slut adjusts himself on the couch and says sit down and I won't say anything. My girlfriend with tears in her eyes, only took off her thong and started sitting on top of his cock, without a condom. As she was going down, she started crying, asking him to stop, but the son of a slut grabbed her tightly around the waist and started lifting and lowering her forcefully. The more she cried, the tighter he held onto her. He kept her seated on his cock for 20 minutes until he had released all the cum he had accumulated. My girlfriend cursed everything and left. The next day she confessed everything to me, saying it was the fault of the alcohol. But later I found out that a few days ago Gero came over while I was at work and the son of a slut gave him ass.