Just note that abyssals do not register undead (without having proper flaw that is). So you cannot tell abyssal being 'undead' with any roll really. Abyssals are living and breathing people, but if you would have essence scanning ability (like All-Encompassing Sorceress Sight), then you could analyze our essence when we use it and with occult lore determine it has same essence like underworld has but would also know it's not same essence pattern what ghosts have/use. So very least could damn us closely associated with realm of the dead with that.<br/><br/>Only best what you could tell from Crow's eyes and fangs that he is clearly a non-human and disturping (yet alluring with Appearance 5). Exalted setting has no lore about vampires so you cannot draw Crow's fangs or eyes mean such traits either (altough abyssals are kind of vampires of the setting).