Thanks, User1.0. That's definitely good advice.

This is something that we have been thinking about for a while. So we have had time to talk about it and to think about rules. We have also talked to other people who have participated in a threesome; and we even attended a discussion on polyamory together. I hope we have done enough to prepare; but I guess I won't know until we try it. I will keep what you say in mind and remember to be careful.

I'll also pay more attention at parties