What defines friends with benefits?

First of all it would probably be a good idea to discuss with him what your relationship is! Otherwise he may think its more than it is and you are going to hurt him. FWB is having or ual activity with someone just for the sake of having . There is no commitment or relationship there, its just about the . Typically in a FWB relationship you don't cuddle or hold each other or sit on each others laps. That is crossing the line of FWB and going into more boyfriend/girlfriend type activities. You need to define what your relationship is with him and what you both want. If its just FWB then you need to stop acting like boyfriend and girlfriend and keep it strictly ual, otherwise someone is going to develop feelings and get hurt.