Back in the day when I (M25) was in a relationship with this complete baddie (F22) I used to fuck her senseless almost every other day. But after a while things started to get boring, it mellowed down. That is when I started to ask her about her friends during sex- who is with whom, who is fucking around the most and so on.
Soon these talks turned into me asking her to narrate her friends' sex stories. There was this girl from a conservative family who had recently started to date and, to my surprise, she had been fucked mercilessly every night by her boyfriend since then. That girl is a real catch. My ex narrated everything from where she had hickeys, to which places and positions her friend was fucked in. I began to imagine her while she narrated their stories when I was balls deep in her.
I don't think she really got the idea that I was imagining her friend ever but she was sus for sure. Nevertheless it was a damn hot thing to do.