as someone who has personally done this, in hindsight its creepy and inappropriate under normal circumstances. From my perspective she's collecting ammo that she may use against you later to say you took advantage of her.
HOWEVER: she is probably just a curious teen (how old is she?) who hasn't had much opportunity to explore or witness the male body, and so she enjoys it when she can. I dont recommend it from personal experience as things can go south, and ESPECIALLY don't get further sexually involved with her; From experience, even if it could be a happy relationship, its NOT worth the risk.
HOWEVER: she is probably just a curious teen (how old is she?) who hasn't had much opportunity to explore or witness the male body, and so she enjoys it when she can. I dont recommend it from personal experience as things can go south, and ESPECIALLY don't get further sexually involved with her; From experience, even if it could be a happy relationship, its NOT worth the risk.