So will a Undead Lord Cleric work in your campaign?  I'm thinking he is lawful neutral - does not animate dead but uses them for good to destroy other undead and send them on their way.  Perhaps he was the son of a mortician who has always been fascinated by death.  As a young apprentice in the ways of necromancy he animated one of his father's corpses he was preparing for burial who then killed his father so he has vowed to keep the dead dead.