Wanting to see my (F26) GF fuck another girl.

Recently I had a sex dream and went like this.

My girlfriend (f 26) and I (m 25) had a night out so we danced, kissed and had a huge Margarita. Throughout the night we ere kinda eye flirting with a girl. When we were back at our apartment I started to go down on my GF and right before she has an orgasms I feel a hand in my ass, spreading my cheeks and putting some lube on her strap on. When I look at her is the girl from the bar (let’s name her Y) we were at and my GF says to enjoy. While I’m being pegged I am able to make my GF cum. We are able to catch a breather and my GF says is her turn pegging me while I eat out Y. I feel her WAP in my face so I tell her to sit on my face while my GF keeps pegging me until I cum all over and Y squirts on my face.

– Back story: My GF has told me how does a FF night can play out and that turns me on a lot. So I’ve been interested in seeing my GF fuck another girl. So I can learn what she likes and how can I be better.