Guy, if you don't like you fwb, why do you get jealous when she flirts/hangs out with other men?

My guess is that this sort of person is being selfish and controlling.

When regarding to people who are in Friends with benefits type of relationships, one or the other tends to either develop some sort of connection for each other.

Women do it just as men, Guy hangs out with girl occasionally, they hook up once in awhile , girl finds out guy hangs out with other girls, she gets jealous and either A) Make a big deal about it or B) avoids the guy altogether.

Guys do it too, I think its a matter of insecurity, People wonder if they're not satisfying enough to meet your preference where he would be your main source of pleasure oppose to multiple guys.

So its either Ego or Feelings, Sometimes a combo of them both, Its always hard to say.

Maybe, but I still doubt that most guys would fall for their FWB. That's just more competition to deal with. The other guy could be taking away his sex object. Also, how do you know that he gets jealous if you said he hides it well? Obviously not if you know about it.