The Vampire's Familiar Chapter 1

"Unlike most humans, familiars are aware of the existence of vampires and choose to act as servants for their vampire master(s), in the hope that they will eventually be turned into a vampire themselves as a reward.

Many familiars will carry out tasks that can be difficult for vampires to do, such as covering up sunlight in their homes, helping them travel to distant places by shipping them, finding other humans for vampires to eat and hiding the evidence of victims."