From Matt's Wife: Well I would never do anything without Matt but we do swing and we started slow by going to a club and having sex while others watched but we went at a pace that we were both comfortable with. Don't ask her to do anything she doesn't want to do.

Sorry, but I'm not a lady but the answer to you dilemma is most likely to keep the fantasy and not push too hard - at least if you want to keep you "girl". If your not married and you don't intend on a long term commitment, then whatever you do to convince her probably won't matter in the long run.

But if you intend to continue in a long term relationship, I wouldn't go much further than seeing her reaction when you tell her your fantasy. And make sure to underscore; it's your fantasy. If she's radically opposed, drop it. If she shows some interest, go slowly, very slowly, and warm her up to the idea a little at a time. If she says, "yea, let's do it tonight', the your fantasy won't be one much longer

Just beware of a couple of important items. Firstly, your telling her you want her to fuck other men which will probably come across at some level as your telling her you don't want to fuck her yourself. It's sort of like telling her she's free to go at any time. Secondly, once she's fucking other men with your permission she may find they're a lot more fun than you. Be sure your relationship is solid or it may not last long.

Good luck.