Haha, sorry! I just don't enjoy stereotyping people. Like, not all lesbians are butch hardcore bitches with mullets. And not all gay guys prance around and talk about fashion.
So in this hypothetical Girl!Bully, I find it entirely possible to have girls as bullies. Being a girl in high school, it's really obvious that girls are bullies. I think anyone currently in high school can attest to that.