I always thought of magic as a sort of energy field that surrounds, penetrates, binds the world together. When you go into a "magical realm" you're having your physical form translated entirely into that energy and existing solely within the field.

I am coming to agree that there's no reason why Vampire Planet has to be a planet, even if somebody's said as much they could easily be wrong or lying. Maybe it's just impossibly far away, and the differences in environment (lack of the Gods / different sun/moons or whatever) result from localised factors. Or rituals.