I fantasize regularly about digging a box cutter into the seats of his new sports car
Why would you feel like doing that to somebody's car?
Because his mother can be quite an asshole sometimes
What does his mother's attitude have to do with his car, I don't understand?  Regardless, you need to respect other people's property and not destroy it.  That could get you into serious personal and or legal trouble.
Shut up. I'm doing what I want.
I just think you're going to get into a lot of trouble if you destroy someone's property. I think you need to let this anger go.