She sent me to bed instead of telling him to leave [cuckold perspective]

me and my gf lived in an apartment building and we met this dude to buy ???? from. I never really liked him. She invited him over to chill and I was pissed so I said I was tired and went to bed. Like an hour later I peeked into the living room and sat him doing ?? off her tits. I kept watching and she did a line off his dick then started deep throwing him. He laid her on her back. Put her legs over his shoulders and started fucking her long and deep. At this moment, I got a good view of his cock. Girthy, veiny, Atleast 3 inches bigger than me. I could see her eyes rolling in the back of her head as she held back moans, cumming on his dick. He then bent her over the couch and fucked her doggy. I heard her whisper “cum inside me”. A few seconds later, he pulled his throbbing cock out and cum came flowing out She stood up. Kissed him and got in the shower and he got his stuff together and left