My bf and I have talked about having a threesome. It's not that the idea isn't appealing, it is on some level and we'd certainly have our pick of pretty much whatever partner we wanted, not be conceited, we are both fit, attractive and young. It always comes back to the same thing: we wouldn't want anything clouding the purity of our love. Making love is so many different things, physical & emotional bonding, an extension of your love. So, the problem (or not depending on how you think of it) is that we don't want to share that with someone who doesn't mean to us what we do to each other. There isn't going to be anyone else who will mean that to either.