My boyfriend and I have been together for about a year. We have talked about being married some day, though we're not engaged. We live together, he knows my family and I speak to his on the phone regularily (they're across the country). We are very close, can talk about anything and have a very... very healthy sex life. We indulge each other in fantasies and we are both ready and willing to discuss new ideas. But for the last few months he has been obsessed with the idea of a three-some.

His best friend's wife recently agreed to having a three-some sometime in the near future (though knowing her, I doubt she'll go through with it. She's very jealous and insecure) so my boyfriend thought that I might be accepting of the idea since our close friends were going to do it too. I considered the idea and talked with him about it a bit and since I didnt automatically go "Hell no! get away from me and never bring that up again!" he is now completely obsessed with it.

When we're out in public he'll point to girls jokingly and say "How about her? She's not nearly as pretty as you are, she's a bigger girl but she looks like she'll be into it." etc etc and then when I get all pouty or react badly he'll smother me in kisses and go "Just kidding just kidding I love you" etc etc etc.

I dont necessarily want to completely axe the idea, I'm open to experimenting with another woman though really I'm not interested in women whatsoever so I wouldnt really want to touch her but I dont like the idea of him touching another her either.. I'm pretty sure I would beat her senseless if he started touching her but I dont want to forget his fantasy because I know that noone should have to let go of their fantasies, they should be indulged before he goes out of his mind and cheats on me. I was thinking that maybe if I set down ground rules like... I choose the girl, I tell them both what to do, he cannot touch her she can only touch him in the way I say (I was thinking maybe us performing fellatio at the same time on him) and he can only have intercourse with me. This way I'm in control, I can stop this at any time and he wont know this woman at all so he wont be able to contact her again.

Now, One of the main reasons I'm saying no right now is because even though our relationship is strong.. we're still growing. I dont think we're strong enough right now to support another person being brought into our bed.

What can I say to my boyfriend to either A) Get him off my back about this fantasy and on to a different one that doesnt involve a third party or B) get him to hold off on this idea until after we're married at least?

Give me some idea of how to deal with this situation. I Do Not want to completely forget about the idea and just say "NOPE, No threesomes for the rest of your life!" because I dont think thats fair for him but what should I do to get him to stop bugging me at least for a couple years?

I'd love to hear from some other women who have indulged their men in this type of fantasy or some women who have convinced their men to change fantasies. Any ideas would be good but I really only want to hear the productive ones... not the people who will just tell me to leave him and move on and blah blah blah.

Thanks!