They aren't? Why are you giving yourself up for doing it? Because I'm really not believing that one for a second.

[He watches him get closer, a small voice was trying to encourage Karkat to take the same steps back to keep him away. But something else in him just tells him to pull his shoulders back and not to be scared.]

Because you're being a dick right now. What's the point of destroying armour? Sure they're about as useful now as a catapult or dandelions. But this isn't your house, those aren't your things. It's called respect, you might want to try it out some time. It might blow your mind because you might actually enjoy it.