Review of Black Butler

In this period piece, an angry teenager brutally avenges himself against a conspiracy through the power of his Bishounen employee. In 'Black Butler' a bitter and furious 12-year old member of the Landed Gentry plots his revenge, Kira-style, on a deranged cult secretly infecting the British Empire. He does this by siccing his hyper-competent butler on them. No, really. It may sound silly, but it's actually awe-inspiring. It works because the two main characters are so well realized. They are both fascinating to watch. One doomed and tragic; the other a razor-sharp cipher. Their relationship, a mutually predatory one, where they tear the flesh off their enemies beforefinally turning on one another.

Ciel Phantomhive, the last surviving member of an Aristocratic Family, serves the Crown as "The Queen's Guard Dog"; a shady troubleshooter, who solves supernatural mysteries in her majesties Realm, by any means necessary. He does this through guile and brute force, without the slightest hint of fear, because he is fueled by an bottomless pool of rage, and a fatalistic acceptance of his fate.

He is "assisted" in this role by the titular Black Butler, Sebastian.
On the surface, Sebastian appears to merely be an extremely competent servant -- a pillar of Victorian decorum and dignity, always dapper and clean -- but can, at a single command from his pint-sized superior, he becomes a whirling engine of terror and destruction.
In this mode, Sebastian isn't so much a weapon, but more like a relentless force of nature. Not so much deployed, rather just pointed in a direction and ordered to demolish everything in front of him.
All the while, he wears a faint smile, as if he is the only one who is in on the joke.
I'd say Sebastian is perfect, with not a hair out of place, but his hair IS perpetually out of place. His character model has a deeply anachronistic hairstyle that is not only out of place for the time period, it is out of place for a butler.
I do understand that his hairstyle is there for the fangirls to go squee over, but occasionally it takes one out of the moment to see a Victorian-era British Butler with a Visual-Kei coiffure.

I think the only real glaring problem with Kuroshitsuji is the comedic elements. There are, especially in the beginning of series, heaping piles of stupid super-deformed slapstick, especially dealing with the other four servants of the Phantomhive household. The cook, groundskeeper, maid and sub-Butler are all varying degrees of loudly incompetent. Most insufferable is Mey-Rin (who is voiced by the usually much better Monica Rial), whose shrill caterwauling will make you scrambling to switch to the Japanese Dubtrack just to escape her shrieky babbling.
Also, their British accents are the most glaringly fake in the whole show.

So, there you have it.
'Black Butler' is what you get when you mix 'Jeeves and Wooster' with a Gothed-out Late 1800's-era 'X-Files'; well, that is if Wooster was a pint-sized Bruce Wayne instead of a buffoon and Jeeves was...well, Satan.

No, that is not a spoiler.
It becomes unambiguously apparent from the frist few minutes of the first episode what kind of Faustian relationship exists between the two main protagonists.
Knowing this makes Ciel's angst (at how far he had to sink in order to avenge himself) more understandable; and why Sebastian's calm, patient demeanor contains a faint whiff of contempt in it. It's not because he's snooty and thinks he's superior to the mere rabble. It is because He IS superior to the mere rabble.
This makes his rogueish charm all the more disturbing.