So there's this girl?

Well if I were you I would act fast and get to know her quick. If your friends bi-curious that she's been hanging out with she might end up experimenting with her if you don't do something quick. Does the girl you like even notice you do you two ever make eye contact. You could also try talking to your friend its a possiblity she might try to hook you up with her if she doesn't already like her.