It's best to assume anything and everything is magical.

On that subject do we have any defined rules on vampires in this setting?
sunlight: nope
holy water: yup (how does it work though?), why does it work in vapor form? why doesn't it work on Johnathan?
running water: ?
garlic: ?
needs to be invited in: apparently not?
blessed metal: seems to work
crucifixes: seems to work
compulsive counting things: ?
stakes: insta-kill? does it need to be a certain type of wood?
Silver: ?
dead man's blood is poison: ?
diseases: ? and if no, can vampires still carry?
smashed in teeth: do the regenerate?
what happens to a human who drinks vampire blood? get high, turn into a ghoul? throws up?
I'm sure I'm forgetting some

and then there's the can of worms of how turning works...