How to tell if a girl is lesbian without asking her ? Serious question.
Very difficult to identify some lesbians, as probably a substantial subgroup of those who call themselves lesbian are in fact escaping from male sexuality after being traumatized, are asexual or identity confused- or a mix of all these.
Some women are uninterested in the physical side of relationships, and the easiest way to find out is to get her drunk, hire a young Brad Pitt to flirt with her and watch for the reaction. Being getbiggers, with looks, money, charm and muscles, you should simply make a move. If she is uninterested- well that is your answer...
NN