Jerome Valeska

"Why did you kill your mother Jerome?"

- James Gordon "Oh, you know how mothers are. She just kept pushing! And I'm like fine mom be a whore, be a drunken whore even, but don't be a NAGGING DRUNKEN WHORE......you know?"

- Jerome Valeska

Jerome Valeska is an antagonist is the Batman based TV show Gotham. Jerome worked at the carnival with the Flying Graysons before killing his own mother due to her being a "nagging drunken whore". Jerome Valeska is supposedly/potentially the origin story of Batman's arch nemesis the Joker, at least in the Gotham series.

Biography
Jerome Valeska's mother was the snake dancer at the carnival, she was known for having sex with any male that worked at the carnival and she was also a hateful and mean woman to everyone around her (although the only proof of this came from Jerome itself so may not be true). Due to her life style and the way she treated him by always giving him orders Jerome hated her and wanted to see her suffer. Jerome finally snapped and hacked her to death with a hatchet. He later faked lack of knowledge of what happened to his mother and faked sadness for her death, although he was eventually caught by James Gordon, also revealing that his birth father was Cicero the blind fortune teller. When Jerome was questioned by James Gordon on why he killed her Jerome began to laugh as if it were all a big joke and told him she was a nagging whore that needed to die.

Trivia

 * Jerome Valeska is the second named Joker adaptation after Jack Napier, he is also the youngest.
 * His implied future as the Joker was also advertised in promotional materials for his debut episode. For example, the trailer mentioned that the next villain in Gotham "is no joke" before cutting to Jerome Valeska cackling, and a Twitter post for viral marketing has a looped GIF of Jerome's laughter from the trailer with the tagline "Gotham's next villain is no laughing matter."
 * Jerome Valeska worked at the same carnival as Batman's first sidekick Dick Grayson the first Robin.
 * Jerome Valeska is portrayed by Cameron Monaghan who is best known for his role as Ian Gallagher on the Showtime comedy-drama series Shameless. 
 * Jerome will return in the second season of Gotham.