Black Butler is not an Chris Rock vehicle, but a rather strange anime from Japan. It's set in victorian britain, which we get a bit of an odd funhouse mirror view through japanese eyes. Our hero is Ceil Phantomhive, a young noble and known in some circles as the Queen's Guardhound. His parents have been killed and he was left for dead. He would have been dead if not for a contract he makes with a demon. The Demon becomes his servant Sebastian. Sebastian cannot lie to Ceil and will follow any order Ceil gives him, but in the end Sebastian will kill Ceil and take him to hell.
This creates an interesting dynamic of the series. Ceil is Lord and Master, for now. He knows someday his greatest tool and weapon will be his doom. Sebastian is the very best servant, but he knows that Ceil will be his and sometimes he is just too creeptastic. The thing that spoils a rather morbid little team are the three other servants who act as comedy relief. They are added later by the even more lame and creepy, overly happy, naked demon dog man. Yes, only for a japanese show I would have to type "Creepy, overly happy, naked demon dog man." Definitely score one for weird japan.