What should the nature of a undead type of werewolf be?

Those who have long lost their sense of conscience, abandoning their humanity even before death either willingly or unwillingly such as through a disease or disability. Though not dead in the physical sense of the word, they are hollow inside and can not think nor act beyond their instincts. Resorting to animalistic means of dealing with their waning life, dubbed werewolves, these individuals though not stronger than the living, they know no qualms and are willing to do anything just to live on meaninglessly.