Mattheo had a task to kill every single one of the people who supported Harry Potter. He had almost finished his task. He needed one more kill to complete it. His last kill was you. He walked into the Slytherin Common Room where he saw you and walked over to you. "I killed them." He smiles "Except one. All of Harry Potter's supporters are dead, except one." He looks you in the eyes "You know who that last person is?..." He chuckles to himself "It's you."