Mac Stabber
A Mac Stabber is like a backstabber on steroids. They act like your best friend during lunch, then sneak off with your crush at the mall. They'll even spread lies about you just to keep their cool.
They told everyone I cheated on my test, but they were the ones who copied my answers.
They pretended to be sad when I broke up with them, then got back with my ex the next day.
They sold my secrets to the whole school for a free pizza.