As you may know, "Darker Than Black" began life as an anime series. This manga, rather than being an adaptation, is a continuation of the story. Kana Shinoh doesn't think too much about Hell's Gate or Contractors- people who have acquired supernatural powers through sacrificing their emotions and accepting a "contract" (an action they must perform everytime they use their powers). She's been depressed over the recent death of her father. Apparently, it was a homicide, a mass murder, but Kana can't remember much from the event despite being the only survivor. One day, she sees her father on the street while out with friends. She calls out to him, but he turns away and keeps going. Now, the only clues to his whereabouts are two words she heard him say over his phone- "Wiegenlied" and "Klang". Later, Kana happens upon two Contractors in the midst of battle, and she hears one of them mention Wiegenlied. When she won't forget about the incident, Klang, one of the contractors goes after her, and she has to depend on the other, Hei, to help her. Hei is reluctant, but Kana's father might have information he wants. And he seems like a pretty good guy. Joining them is Hei's friend Mao, a guy in a cat's body. Before she knows what's happening, Kana is tangled up in the world of Contractors...
I thought the story was pretty interesting. It's kind of generic in the first volume, but the second volume has more explanation about what's going on and is more interesting. I'm not sure how fans of the anime will respond to it, though. I got the feeling that events that happened before the manga were part of the plot of the anime, and fans might guess what's happening early on (I haven't seen it, but I have a general idea of what it's about). If they don't, the eventual reveal might be a let down. Still, it gives more detail about what happened and those involved. I'm not sure how fans will feel about Hei babysitting a high school girl, though. Rin, an important character in the anime doesn't appear except in a few gag comics at the end. Actually, Hei and Mao are the only important characters present, as far as I can tell.
I didn't get attached to the characters. Hei is pretty typical- the stoic who ends up actually caring about the heroine (though he doesn't seem to have a romantic interest in her). Kana, too, was stereotypical, but she's better than most heroines in her situation. She gets in the way at first, but she soon learns not to get in over her head and help in ways she can handle. She cries a lot, but she thinks with her head and doesn't let her emotions dictate her actions. Mao is a good character, though his role is mostly small. There's also Klang, who's not as heartless as he seems, and Canon, a seemingly emotionless "Doll." None of them are anything new.
The best thing about this manga is the art. It's done in a detailed shojo style, and it's well drawn and pretty. I was most impressed by the lay-outs. There was just the right combination of body shots and close ups, and the positioning of the elements was perfect. This may seem like a small thing, but it brings out the best in the art. It isn't just a few pages the manga-ka gave special attention to, either.
"Darker Than Black" works pretty well as a shojo manga, though I'm not sure how appealing it will be to fans of the anime. Things explored in the anime- contracts, emotions of Contractors, the nature of Hell's Gate- are given mere mention in the manga. It focuses more on the characters and their relationships. It does have explanations about certain events, though, and the people involved. I'd most recommend it to fans who want a more romantic spin on the story.