Trigun is an anime that aired on Cartoon Network on Adult Swim. It's story line is hard to follow because each character has a different objective.
Vash The Stampede destroyed the city of July by accident with his angel-arm, and a rather large bounty was put on his head. Vash's goal is to gain money and not to get killed by all the bounty hunters after him.
Meryl Strife and Milly Thompson were sent from the Bernadelli Insurance Company to find Vash the Stampede and reason with him to stop doing damage to citites.
Nicolas D. Wolfwood offered to be friends with Vash and is a traveling priest trying to find orphans and make money for the ones at his church already.
Millions Knives, Vash's twin brother, and the Gung-Ho Guns are out to kill Vash and kill every human.
All of these weird plots twisted in one make one big plot. Knives and his minions try to kill all humans while Vash, Wolfwood, Meryl, and Milly try to stop Knives from destroying the world.
Then there's Kuroneko-Sama. In Japanese that means Lord Blackcat. The goal of Kuroneko is to apear in every episode. And do the meow that made him famous. "Neaw!"