Mr. Conjure - The Scary Mary Series, #6

"I've never heard of Mr. Conjure, " Mary said."He creeps through the shadows wearing a raggedy top hat and a long black coat. His claws are stained a bright red from all the blood he's spilled. If he gets you, there's no escape.""Why's he called Mr. Conjure?" Mary asked."What do you mean?""Why isn't he called Top Hat or Mr. Red Hands?"Eddie frowned. "Because he's called Mr. Conjure." "But what does he conjure?" Mary asked."He doesn't.
You conjure him.""But why would anyone want to?""Because people are sometimes stupid, " Rachel said. Jenny is a little stupid, at least that's what Mary thinks. Why else would the teen go to an abandoned house by herself and play a game to summon a monster called Mr. Conjure? Mary doesn't believe he exists, but Jenny insists that he's out to get her. She's so afraid of him that she attempts suicide. Rachel wants to help Jenny and needs Mary to do it.
Mary thinks Jenny needs a shrink, not her. She's sure Mr. Conjure isn't real. But something is lurking in the dark, and if it can't get Jenny, it'll take Mary instead.