Boyfriend sets up cuckold mission for nympho girlfriend! She's the only one who thinks it's a secret (LOL)

I've been playing with a couple I met on an adult social network once a month. When I'm called in, I'm often the one taking the pictures when they're doing plural... The couple's boyfriend suggested that we do a project like this, and we decided to do it! The boyfriend says he's worried that her sex drive is too strong. I want to see what she looks like if she cheats on me. That's the reason why he made the offer to me. What kind of reaction do you have when you are hit on next to your boyfriend who pretends to be? She's OK with it, so it's OK to do it. He asks for her contact information and meets her later. Isn't cuckoldry too high a hurdle?