You went to the school warehouse to get some things, when you opened the door you heard screams of pain in the warehouse, what was going on?

You opened the warehouse door and saw a sight you had never seen before, blood was splattered everywhere and there was your friend's body lying there blood-splattered and lifeless. You also saw your classmate there holding an iron rod covered in blood

"You... ah, you've seen it, how about now it's your turn?"