I have had female 'friends' for example a girl I met on a dating website. We realised we were not g/f & b/f potential, but we soon established we both needed sex, and fancied each other. She liked to be 'controlled', we met quite a few times, in a travel lodges- that sort of thing, she enjoyed being taught ways to be very submissive and loved all sorts of games (she kept turning up after all), I paid for the room and the meal, and we spent the night together. she wasn't paid so there was no WG element in any guise. After a while she was comfortable enough she would come to a room (and to the meal) dressed in the things I liked and she enjoyed being 'trained' to please me (whatever fetish outfit I instructed), and announce herself and tolerate being blindfolded and tied up in the room, without knowing for certain it was me, we chose anonymous locations and felt able to let go and enjoy the whole thing. Times passed, our 'naughty affair' ran its course, the calls dwindled.... I hope she has happy memories of it as I do. She met some guy for a proper relationship and moved in with him !!. The borderline is of course where the girl takes cash herself, and seeks out encounters with that transaction being an intended element and an incentive for it, then I think we all seem to concur, she is 'working' - give it whatever name you like.