My friend asked me to have sex with her bf

I'm in a long distance relationship my friend has been in a relationship with this guy for over 3 years and thinks she might be into the whole cuckquean thing.

I wasn't judging her I told her she should talk to him and try something out. then she asked me if I would be comfortable having sex with him I was shocked by this. I told her I didn't know if I could do it but I did find him attractive which turned her on to hear

I ended up giving him head in front of her that same night. she came while watching us but I didnt let him fuck me because his dick is entirely too big I'm kind of regretting my decision to even partake in whatever the hell that was lol.