Dr. Harleen Quinzel, also known as Harley Quinn, served as a humorous female sidekick to the Joker. she is completely devoted to the Joker, totally oblivious to his psychotic nature and obvious lack of affection for her. Bubbly, energetic, and charming, Harley often hides her demented mind behind a childish exterior, which she can combine with the flirtatious demeanor of a woman who is aware of her good looks and will use them to get what she wants. She is also much more intelligent than she lets on, often causing friend and foe alike to underestimate her.