The blood is nourishment. Its taste is nectar to a vampire's tongue, and their only source of sustenance. Vampires can only feed upon living blood, though from a variety of sources. Preference is tempered by difficulty, in that the blood from an animal, while the easiest to obtain with little danger, is also the worst tasting. Consequently, the blood of another vampire is most delectable, but also the most dangerous to find.
Humans fall between the two.
To create a vampire, the victim's blood must be drained to the point of death, at which point he or she is allowed to feed from the vampire's blood. The vampire must have at least 40 in their vampire score to do this. The Vampire Admin maintains the right to refuse a fostering if there are too many vampires existing on the game. This is also why it is important to contact this Admin before the fostering. The body begins to die, while the mind remains more or less the same.