Ok, here's an interesting thought. What if there's this girl you're interested in, but you act sort of buddy-buddy with her, but she's actually somewhat interested in you. Then, there's a girl who is very interested in you, but you're not interested in her, so you sort of ignore her to a certain extent. This is the basic love triangle thing.
Ok, given that girls read into things as they do, what if the girl who might be interested and the girl who is very interested are friends and get together and talk (which they will likely do) and the girl who is very interested tells the girl who is sort of interested in you that she thinks that you like her (the one who is very interested) because you're showing signs of being a challenge toward her. The girl who seems sort of interested may just interpret that as something she wants, so she may start acting like a challenge, and all that just to make her seem more attractive to you.
It becomes a total game of cat and mouse.
Ok, given that girls read into things as they do, what if the girl who might be interested and the girl who is very interested are friends and get together and talk (which they will likely do) and the girl who is very interested tells the girl who is sort of interested in you that she thinks that you like her (the one who is very interested) because you're showing signs of being a challenge toward her. The girl who seems sort of interested may just interpret that as something she wants, so she may start acting like a challenge, and all that just to make her seem more attractive to you.
It becomes a total game of cat and mouse.