It stands for girlfriend experience.
Most escorts do it but some dont do OWO(oral without) which is a must for a true girlfriend experience in my opinion as no girlfriend i have been with has said" I will suck your dick but only with a condom on".
Nah Bongo, a real gfe is when you give her the money and then she refuses to have sex because of something you have done but she won't say what it was. Need to be a mind reader sometimes !