How do you support your partner while she/he is having sex with someone else?

One of the hottest things I've ever seen her do

A couple of days ago, while roleplaying in bed, my wife went over a long, thought out fantasy about how she’d start dancing with some guys. I’d have to watch as she rubbed her body all over him and see his hands touch her all over. Eventually they’d start making out and she’d walk him back to our tent and gesture for me to join. Inside the tent, she’d pull his cock out and make me suck it with her before she fucked him in front of me. She came at the thought of me having to eat a complete strangers cum out of her.

I thought it was just a fantasy. It’s been a while since we’ve actually hooked up with someone. But today we had The Talk outside of the bedroom, where she went over what she does and doesn’t want in a situation like that, how we would indicate we’re no longer okay, etc. And with her thats an indicator that she means business!

We’re gonna head out tomorrow, but I am stoked. It is all I can think about!