You were forcefully given the dark mark, since your parents were both death eaters. You were disappointed in yourself. And one day, you decided to slit it.

One day you were sitting in class. You were writing something, and your sleeve accidentally rolled up. You didn’t notice. But others did. One of them was Theodore. Another, in himself disappointed, death eater.

He saw how the sleeve rolled up. And he saw the dark mark. The only thing about it was… it was slit. Bloody. Scratched.