[FMM] How do I ask my boyfriend I want to have a threesome with another guy?

So my boyfriend (M26) and I (F24) have been together for 3 years now and for some reason I can’t stop thinking about having a threesome with one of my friends (M27) but I don’t know how to ask either of them.

I would always joke around with my boyfriend saying, “babe let’s have a threesome” and he agrees only if it’s with another girl (which I’m open to try too) but I want my first threesome to be with another guy or maybe a foursome?? LOL.

Anyways I have this guy friend that’s totally hot, almost as hot as my boyfriend and every time I see him at parties I can’t stop thinking about fucking the both of them. I think it’s because I want to try something new since me and my boyfriend have been together for awhile and he’s been the 4th guy I ever slept with. Don’t get me wrong though, my sex life with my boyfriend is AMAZING, something every girl should experience.

I don’t know how to tell my boyfriend without him feeling like I want to have sex with someone else because he gets jealous and tells me he doesn’t want to share.