It's because when we sneeze, our soul flies out our nose and if no one says 'bless you,' the devil can snatch it.
Nuh-uh. No deals with the devil. I’ve learned my lesson on that one. ~Jaime Vegas
The upshot of her tirade was that I was the devil's spawn and should be locked up in a tower before I unleashed hordes of the living dead to slaughter them all in their sleep. Well, maybe that's an exaggeration, but not by much.