Doggy style GFE: He sits up and begs, then she rolls over and plays dead.
Badda boom!
Seriously, I'll
quote and paraphrase the
words of Maggie McNeill, aka
The Honest Courtesan
GFE is subjective, but generally means that the escort will cuddle, kiss, refrain from obvious clockwatching, and generally make the experience seem much more natural and less mechanical.
I don't think GFE is defined by the inclusion of particular mechanical acts, such as DFK.
GFE is essentially a performance, no different from acting or singing. For most of human history the majority of actresses were also harlots, and though the professions have diverged to some degree the whore (especially the call girl) is still essentially an actress in a private erotic drama, with the customer as her audience rather than her equal partner.
Clients seeking GFE want to feel the sense of connection which can only result from honest personal interaction, the feeling that they are spending time with a real human being with hopes, dreams, loves, sorrows and quirks which make her a distinct individual. The competent professional knows how to strike the perfect balance between illusion and honesty which will give her client the most memorable and satisfying experience possible.
Like a film actress a great whore must draw upon her own personality and experience in order to create a true interaction with her client, and unlike her actress sister she must do so without either a script or a director to guide her.
Put another way, the clients seeking leather-clad mistresses to bind them, tease them, and/or humiliate them are seeking one kind of performance. Those seeking GFE want a different performance. A skilled whore can serve both audiences, changing her costumes, persona, and style of interaction as each role requires.