Black CatBlack Cat.

Black Cat (stylized in all caps) is a Japanese manga series written and illustrated by Kentaro Yabuki. It was originally serialized in publisher Shueisha's shōnen manga magazine Weekly Shōnen Jump from July 2000 to June 2004, with the chapters later collected into twenty tankōbon (bound volumes) by Shueisha. The story centers on a man named Train Heartnet who withdrew from an elite group of assassins called the Chronos Numbers to become a bounty hunter.