one, two, three, ACTION!

so last night, my ex and i were talking about what movie we are going to see for his birthday, yadah yadah, long story short he said he would sleep with me, but only in a threesome situation.
wtf?
i had to explain why i was offended by that comment.
i came up with what i now realize was a lame analogy.
"so basically, it's like if i make an apple pie, and you're like hell no. i'm not eating your pie. f*ck that. but then you see this naked girl eating my pie, and you're like, okay, i'll have some of your pie, but only because this naked girl is having some." his response was something to the effect of...he couldn't sleep with me one-on-one because there would be emotions involved. whereas in a threesome situation it's purely physical. so it's not that he hasn't wanted to "eat my pie" it's just that he thought it would make things too hard and we wouldn't be as close as we are today.
"fine....but that's still f*cked up, you know that, right?"
yes, he said.
when are trios a good idea? if it involves people that you have no emotional baggage for, then i guess they're a fine pasttime (if you're the adventurous, non-jealous type). however, i can't even remotely imagine doing that with someone i care about. seriously?? and who is the third party supposed to be? certainly not someone he knows because he's probably already messed around with her or has been wanting to, and i refuse to be a party to that. and it can't be one of my friends because i don't want to know the terrain, texture, hills and valleys of my friends' snatches (or any girl's for that matter). and i don't want him to either. and it can't be a stranger because that's kinda gross. and what do you do? put an ad on craigslist?

wanted: female to be third leg in FMF love triangle. must be clean. hot enough to get the guy excited but not so hot that she makes the girl feel insecure. must be good in bed but not so good that she outshines the other girl. must be willing to leave immediately afterward and never try to make contact again.

plus, i'd have to use a fake name because i wouldn't want her going to the enquirer when i'm all trying to win my emmy. and what on earth am i supposed to do while they are having their "time?" do the soundtrack? applaud? stretch?
i know this is a common occurrence, so i'm not knocking it or dissing it. i'm just curious.
i hate to break his heart. he was so excited by the mere prospect, like a pup who smells sausage on your breath.
but i can't.
i'm not going down like that.
i'm not going down at all actually.
i didn't know it took three people to get one person laid in L.A.