A person who can "throw" their scent and make it seem like it comes from someone or somewhere else. It could be a perfume, a belch or, at worst, flatulence. Often it could be that the scent is so strong that someone else's clothes absorb it as they pass through it.
"Wait, did you have garlic for lunch?"
"No, that was Greg who just walked by. He's a scentriloquist after he eats Italian."
"Okay, is everyone wearing Lovespell at this party?"
"No, just Tracy. But she hugs everybody. She's a Lovespell scentriloquist."
"Don't get a lapdance from that stripper--she's a scentriloquist. Your girlfriend will know you were here."