Dremora Butler

 is a Daedra encountered in.

Black Book: Untold Legends
He can be obtained as a reward for the Black Book quest Untold Legends.

He can be summoned using the Secret Servant power. When activated, he appears and offers to carry any items for the Dragonborn, much like a follower would. His carry weight is however capped at 148.

Quotes

 * "Ah, a new master. It's been centuries."
 * "Oh look. My new master."
 * "More cups and plates for me to carry?"
 * "I don't suppose you'll carry some of this for a while."
 * "I live to serve."
 * "I've always dreamt of being a pack mule."
 * "It's been so much fun."
 * "I'll be going now."
 * "A butler's work is never done."
 * "Certainly, ma'am" (if the Dragonborn is female)

Trivia

 * True to his profession, the Dremora Butler behaves much more refined and polite towards the Dragonborn than any other Daedra encountered in-game. Also, his voice does not sound menacing, unlike his fellow Dremoras.
 * He will often give out snide remarks about his job as the Dragonborn's butler.

Bugs

 * Sometimes one or more items given to him will be missing from his inventory upon subsequent summons.