Definition - What does YMMV Girl mean?
A YMMV girl is a sex worker with a reputation for being inconsistent in attitude and service. YMMV means "your mileage may vary." It indicates that a client's experience may vary from that of other clients. While this is generally true in most cases, a YMMV girl is someone who may have received a variety of differing reviews based on their lack of consistency.
Kinkly explains YMMV Girl
YMMV is often utilized in escort reviews to indicate "This was my experience. Don't blame me if yours is different." That is different than the use of the term YMMV girl which is used as something of warning about specific sex workers.