The Beast
Vampires owe their existences to the blood of the living. When they rise from the dead immortal, they are imbued with a supernatural and fierce hunger. This hunger can never be satisfied, not really. It can only be fought. Vampires call this The Beast. Unchecked, this hunger is so strong that it will reduce a vampire to a savage, unthinking fiends who drink their victims dry in sanguine savagery. This Beast is a constant companion throughout eternity.
Vampire Roads are deeply personal philosophies that help keep The Beast at bay. The Road of Humanity is a common road, but it is just one of many.