Originally Posted by PolyinPractice
I've had FWB relationships before; they could be ended by either person, for any reason, at any moment. To me, that is casual. There was no "relationship"; just sex.
In my personal terminology I wouldn't describe that as FWB - since there is no "relationship" and I consider friendship to be a very significant relationship. I'd consider a person like that a FB ("fuck-buddy") (or, when I'm feeling mean "Dick-On-Call").
Again, it doesn't really matter what you call it - as long as you define your terms (when discussing things on a board like this - where people may define terms differently) and everyone is in agreement about what the expectations are.
PS - I just have to point out, to be brutally honest, ANY relationship can "be ended by either person, for any reason, at any moment
" - it takes two to tango. It's just that in a casual-type situation that is more expected and less painful.