_Villains
Harley Quinn
She becomes fascinated with the Joker while interning at Arkham, and volunteers to analyze him. She falls hopelessly in love nearly instantly with the Joker during their sessions, and she helps him escape from the asylum more than once. When the Joker is returned to Arkham after a battle with Batman, the sight of her badly injured patient drives Harley to don the costume and become Harley Quinn, the Joker's sidekick and on/off girlfriend. She later becomes fast friends with Poison Ivy, who injects her with antitoxins to give her the same immunity to poisons she has (which explains why she is not affected whenever the Joker releases his lethal laughing gas).
Harley Quinn
She becomes fascinated with the Joker while interning at Arkham, and volunteers to analyze him. She falls hopelessly in love nearly instantly with the Joker during their sessions, and she helps him escape from the asylum more than once. When the Joker is returned to Arkham after a battle with Batman, the sight of her badly injured patient drives Harley to don the costume and become Harley Quinn, the Joker's sidekick and on/off girlfriend. She later becomes fast friends with Poison Ivy, who injects her with antitoxins to give her the same immunity to poisons she has (which explains why she is not affected whenever the Joker releases his lethal laughing gas).