I kind of think that'd be interesting. As long as it's a blood type that agrees with them. Imagine brewing coffee with Rh-negative blood.
Their night would be their "day," while their time to sleep would be their "night." Call it living an inverse.
Like, say, if a vampire comes up on a human and starts to drink, they could spit it out because it's a blood type they hate the taste of. Or if a vampire prefers Rh-negative, they would probably be excited when a human has that.
There's obviously more than the common blood types, but let's just use those for example. Maybe some could prefer Type A for having a rich flavor. Or Type O for being salty.
Took me a bit to get the joke lol. But I remembered that one song. "E eats everything," I think that's what that song was...
The witch, and the tank enthusiast. The latter could be like Tank Girl...
Technically I'm a transmasc cat enby, but close enough to being a trans man.
My pronoun sets are they/them and it/its. It sounds weird to use the latter, but nothing wrong with nullifying the negative of the "it" set, right?