The Bloody Baron

Slytherin's ghost, The Bloody Baron was terrifying in appearance. The silver blood on his clothes was a clue to his death, and the horrible crimes that preceded it. Sent by Rowena Ravenclaw to find and return her runaway daughter, Helena, tragedy struck when she refused to go home with him, ending in her bloody murder. The Bloody Baron then killed himself in deep regret, returning to Hogwarts as a ghost and carrying heavy chains as a symbol of his repentance.