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Nightmare Fuel: Death Masks
Shiro's death by torture.
Harry's been tricked by Nicodemus into touching one of the cursed coins, meaning he's now got a copy of a Fallen angel in his head. He's not about to let it start him tempting him, but just as he's about to bury the coin in the floor of his lab, a voice whispers in his head. It only says Harry, but it is nonetheless extremely creepy.