I have been in both situations (FFM and MMF) and there are a couple of important points to remember

1) Everyone should have clear understanding of what's expected. If a couple is bringing in a third, everyone needs to know if emotional committment is expected or to be avioded, etc. This can keep a committed relationship from getting into trouble, and can keep people from getting emotionally hurt

2) Everyone should be sure that they are staying within their comfort level. An ex-boyfriend of mine let me indulge in a threesome with him and a friend of mine, but he was never very comfortable with the idea, and it ended up being a breaker for our relationship.

So, to answer your questions, yes I would always be open to any suggestion of a threesome, but my personal preferences tend to go that way. Would I like to see two guys play around in the threesome? If they thought it was exciting, absolutely it would be a turn-on for me. If the guys were at all squeamish with the idea, then no, because it would ruin the experience for everyone.

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Thank you, sir, may I have another?