Is it okay for Elliot to take notice of the death energy around your character if they have it for reasons like being a vampire or undead or ill, or for whatever other purpose they may have it? (If it's not, I'll just play that he'll ignore it. And just because he does notice it doesn't mean he'll out them at all, he's a witch that's likely to try to eat your dead grandma, he's not gonna be airing out people's laundry. ):

Okay. So.

Vanessa's blood is described as being the antithesis of vampiric in her canon. She can cure vampires if she bites them or they feed on her, and they're immune to vampirism forever after that.

That said, she's 'died' four times for varying amounts of time. During that, her blood continues to function as if it's alive, but her heart is stopped and she's in what seems like a death coma.

In regards to Eliot, you can take this however you think he would. She should be dead several times over, but she can come back from any damage done to her body.

Would you be interested in pursuing CR with Elliot trying to whip up some kind of feeding arrangement? (i.e. blood for death.): She doesn't need blood to survive. If she's helping him out here, though, she might tell him to pony up if she needs the extra power-up temporarily.