If vampires and werewolves are astral beings [I have never seen one but am told they are] then its probably similar to Dragon Magick where you call on them for guidance and during rituals/spells. [similar to calling on a deity] Just a guess though.
I've also spoken to people in the path who claim to either have an animal spirit, or work with animal spirits/energy and some call themselves werewolves though they do not believe they can physically transform, they do claim when they project their astral self is a wolf [or whatever animal spirit they claim to have]
For the people who claim to be sanguine vampyres, or work with vampires, normally live like a Dracula vampire [work night jobs, dress in black, wear fangs, drink blood] but they are human. They would normally work blood magick too.
I've never worked with either, nor do I claim to, but I think that's what they mean; work with the astral beings/energy.