Black Cat - Kentaro Yabuki

Train Heartnet, also known as "Black Cat," was an infamous assassin for a secret organization called Chronos...until he abandoned that cold-blooded existence to live on his own terms as an easygoing bounty hunter. But is Train's past as far behind him as he thinks?

Train and his partner Sven go after a huge bounty, attempting to track down a weapons smuggler who is dealing dangerous new technology on the black market. They cross paths with an elegant thief who offers to help them, but will the alliance be fruitful, or will the burglar bring bad luck to Black Cat?