Gained a Couple Battle Scars

Emberly is a muggleborn witch with metamorphmagi abilities. Despite somehow being placed in Slytherin, shes made friends with the Weasley twins. During her fourth year at Hogwarts an unforgivable curse was shot at her making a scar appear on her that wasnt there before. If its touched it turns black and she turns dangerous. Theres only one person who can touch it and make her go back to normal, George Weasley.