What do you do about a kid who has stolen your seat in cl?

I walk into my anthro cl (I was away for a few days) today and I was about to sit in my usual seat when I notice a bag there and my friends quickly tell me to not sit there and tell me "it" sits there now. I didn't know who they were talking about until the kid (biologically a girl, TRIES to be a guy ~shaved head and wears guys clothes and everything...) walks towards us. I quickly move away and sit in the front. Thing is I want my seat back...it has a great view of the girls in the cl and right next to my boys so....How do I get "it" to move? I would beat it up but I don't hit girls...(?) I'm sorry, I'm confused what gender to refer it to. Should I ask the teacher to move her somewhere or would I come off as a bigot...some guidance anyone?