With that sadly necessary disclaimer out of the way, let's discuss Kuroshitsuji. Kuroshitsuji is the story of a boy named Ciel Phantomhive, and his butler, Sebastian Michaelis. Ciel is the head of a toy company, and is also in the employment of the Queen, who enlists him to deal with various mysteries. Why this is the case isn't really explained, but nonetheless, most of the episodes play out as a Sherlock Holmes style detective series with him solving various supernatural mysteries.
Of course, Ciel is no ordinary boy... he has a contract with his butler for his soul. As you probably already knew, Sebastian is a demon of sorts. He is nigh invulnerable to everything, has amazing skill in pretty much every field, and is basically perfect in every way.
This, however, is the first problem with the series... Sebastian is a massive Gary Stu. He's simply too perfect. Not once do you feel for him as a character. He is completely overpowered, and is essentially an end all, fix all solution to more or less every single problem the series can throw at any of its characters.
Sadly, the rest of the cast isn't much better. Ciel Phantomhive is probably the most likeable character in the show, being something of a snarky, deadpan character with a chip on his shoulder the size of Africa. But he has his idiosyncrasies as well... most of which simply come down to him being a complete jerk to everyone. Ciel is generally single-minded, only caring about whatever mission the Queen has given him, or getting revenge on those who ruined his life. The reaper, Grell Sutcliffe, had potential to be a loveable psychopath in the vein of Ladd Russo or any given Hellsing villain, but they eschew the chainsaw wielding, slasher smile route laid out in front of them in favour of making him incredibly, incredibly gay, as though they were trying to make a psychotic badass Leeron. But unlike the aforementioned Gurren Lagann character, they don't manage to make him nearly entertaining or tongue-in-cheek enough... to be perfectly honest, Grell is just plain offensive.
Another problem with Kuroshitsuji is that it can't seem to decide what it wants to be. For half the series, it goes down the aforementioned Sherlock Holmes route, painting a great depiction of 1888 London, rolling through themes like Jack The Ripper and Scotland Yard, but for the other half it tries to blend a Tim Burton-esque supernatural demon theme to the mix, and the tone of the series becomes very inconsistent as a result. Both styles are well-executed, but they conflict with each other. If they had been more consistent, Kuroshitsuji would have been better as a result. The character designs also mirror this quite heavily; While we often get a good, 1800s design like Sebastian, we also get overblown, colourful and vibrant designs like those of Grell or the Undertaker that creates a very poor contrast.
Also, there's something that can occasionally be very jarring, and that would be the anachronisms. Despite the show being set in 1888, you will frequently see things that are very out of place in this time period, like advanced modern handguns, sophisticated chainsaws, and film. While all of these things did exist in some form at this point, none of them do in the form they are shown in. And even more jarring is that most of these are applied to the Reapers, ancient beings that would not realistically incorporate these sorts of things into their supernatural array of weapons.
And on that note, one of the things that annoys me most about Kuroshitsuji is that the demon lore is left completely unexplained, as though they were some sort of afterthought. The reapers hate demons, but why? It's never given any real mention. There are also Angels, only one of which we ever see, whose purpose and role in the demon lore is never even touched upon, let alone their motives. I think Kuroshitsuji would have actually been better if they had completely left out the angel/demon/reaper aspects of the show and solely focused on the detective angle instead.
The only aspect wherein Kuroshitsuji really shines is the production job. The animation is fluid, and the art style is thoroughly polished, using a blend of dark, rich tones. The 1800s environment is one of the strong points of the series, which makes it all the more of a shame that they so often opt for the Burton-shtick instead. The soundtrack is also very strong, featuring a variety of music fitted to the period, most notably the smooth jazz.
Now, before this reads like an invitation for all the yaoi fangirls to break down my door, let me just clarify this by saying that Kuroshitsuji is not bad. What it is is average. Ordinary. Run of the mill. The only exceptional thing about it being the insane level of fan-pandering it stoops to.
However, there is still one serious problem with Kuroshitsuji not accounted for... the ending. The last few episodes are an evermounting pile of contrived nonsense. Things happen, but no explanation as for why or how is ever really given. No character's motivations ever make sense. Plot twists come from absolutely nowhere with no foreshadowing or real explanation. It rivals Soul Eater in terms of ridiculous bullshit endings, but at least Soul Eater didn't leave us on an incredibly dodgy cliffhanger that leads to a second season of pure filler.
Final Words: It had potential, but it ignored it so it could pander to fans.
Animation/Graphics: 9/10
Story/Plot: 3/10
Music/Background: 9/10
Overall: 4/10
For Fans Of: Hellsing, Pandora Hearts.
