Why are cat's seen as sexy

I mean when you say that someone is ugly, you say they are a dog. Yet the whole cat woman thing is supposed to be sexy right? And when to chicks fight they call it a cat fight. Now I'm willing to conceed that its totally sexy when two chicks fight... but its not sexy when two actual cats fight. Trust me, I watch the discovery chanel sometimes. I don't know, maybe I'm thinking about it too hard.