
^Anime ------------------------------------------------ Manga^
I don't have too much to say about this series, other than that both the anime and manga versions are pretty awesome (and very different from each other, as well)
Both the manga and anime follow a person called Train Heartnet, who used to be an elite assasin for an organization known as Chronos, known for bringing bad luck to his victims. He earned the nickname "Black Cat" due to his skills, as well as his position in the Chronos Numbers as number 13 (XIII). But eventually he left Chronos after meeting and spending time with a sweeper (bounty hunter) named Saya Minatsuki. She was Train's inspiration into becoming a sweeper himself, especially after some events that happened just after leaving Chronos. In the manga, he ended up meeting with and teaming up with another sweeper known as Sven Vollfield a little while after those events occured, while in the anime the timing of all that happened with Train, Saya, and former Chronos associate Creed Diskenth was different, and happened generally around the same time as when Train first met Sven. The story basically follows Train, Sven, and the young nanotechnology-infused girl named Eve, as they try to capture bounties, and somewhat go after Creed Diskenth and his group known as the Apostles of the Stars.
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This really is an awesome series, because of the great characters in it. Train kinda reminds me of Vash the Stampede in some ways, but is also different in some ways. Sven is also an interesting character, always acting as a "gentleman", and in the anime, he ends up being like the comic relief a lot, as well. Eve is also really interesting, as her nanotechnology-based transformation powers are really cool, and her monotonous/deadpan style of speaking, combined with her facial expressions at times, are hilarious, and also add to her awesomeness. There is another kinda-main character, Rinslet Walker, who also shows up a lot. She's the purple-haired lady in the above pictures, and is a master thief
The manga is decently long (20 volumes), and is a very good read. The anime is relatively short considering the manga's length (it's 24 episodes long, with the manga plot basically taking up only the first 20 episodes), and is considered by quite a few people as inferior due to it's compressed nature. Though I think it's very very much worth watching, because it's really pretty to watch (especially the final conflict episodes with Creed), and just overall really good in a different way than the manga. Just don't expect them to be too similar, if you read the manga and watch the anime.
I very very highly recommend watching and reading this series. I don't know which you should go through first (as I kinda went through both the anime and manga at generally the same time), but I do think it's probobly good to watch an episode with Eve to catch her style of speaking, so you could picture/hear it perfectly when reading the manga.
I don't know how much of the manga has been released in stores, but I know Naruto Community has all the volumes in fan-translated english... As for the anime, I believe the English dub of most of the episodes are currently on sale and available to buy, and you could probobly torrent 23 of the episodes, fansubbed (the missing episode, which is officially the 15th episode of the series, originally wasn't aired in Black Cat's first run in Japan, though it was released on the DVDs, and aired by the channel that carried Black Cat in it's later runs; but since it wasn't part of the original run, it wasn't fansubbed).