My girlfriend and I are both bi. A couple of years ago we got into swapping and sharing, and one of the first things we experimented with when we started exploring that was watching some videos of her sucking her ex boyfriend’s dick. Stop me if you’ve heard this one before, but his cock is amazing. Big and beautiful.
We moved from watching the videos into role playing about it, sometimes we’d watch the videos while fucking and she’d narrate the videos while riding me. Eventually we both got so horny about the idea we decided to reach out to him to see if we could get some more of his big cock. My girlfriend talked to him first, and as she suspected, he didn’t want anything to do with me, but was willing to just talk to her.