Mad Dog (Courage the Cowardly Dog)

Mad Dog is the main antagonist of the Courage the Cowardly Dog episode, "The Mask". He is an anthropomorphic dog/pimp who took Bunny away from Kitty to be his lover/prostitute.

Biography
Mad Dog is a pimp and crime lord who kidnapped Bunny from Kitty due to jealousy and made her into a prostitute. He forced Kitty to leave town as well. It was because of him the Kitty believed all dogs were evil. Any time she did something such as try to escape, he would punish her by burying her in a flower pot, leaving only her head to surface.

Being scarred by Mad Dog's actions, Kitty arrived at Courage's house, repeatedly beating him due to being under the notion that all dogs are evil. After Muriel invites her to stay at the house for a while, Courage is desperate to find a way to get rid of her. After he finds Kitty's squeaky toy (a gift from Bunny) he manages to find Bunny in Mad Dog's apartment after she's been put in a flower pot for trying to escape. Courage helps her out, but not before going through Mad Dog's minions.

After they escape to get to the train that Kitty's on, Mad Dog chases both Bunny with his car and kill her, but Courage dives through the window and spun the car onto the railroad tracks. An approaching Amtrak passenger train destroyed the car and left Mad Dog laughing foolishly on the Amtrak Passenger train's diesel powered steam locomotive. It is unknown if he survived or not.

Trivia
Although Courage the Cowardly Dog was never exactly kid friendly, Mad Dog stood as one of the show's darkest villains, bar Katz and Fusilli. This is due to him being the only pimp in an animated family program, and being taken seriously as such, even is his methods of punishing Bunny were over the top and cartoony.