Cucking trade off

I was just wondering if anyone else has had this experience…
So I’m currently in my 6th year of college (going to school for pharmacy) and last year when I was living in a dorm I had the biggest freaks of the whole dormitory on my floor, I ended up being friends with them and I later started dating one of the girls. I caught her getting her ass and pussy ate out by her friend and I was a bit upset but she said it’s ok cause she’s a girls and that we should all get together, so I did. And now we’re a year and a half strong as a swinger couple after we talked about it. I get to fuck her and abt 5-6 of her friends who are also into stuff like this and she gets to fuck one of my friends. Has anyone had an exchange like this ?