In the world of Batman comics, the Joker is a notorious villain with a twisted sense of humor and a complete disregard for human life. Over the years, the Joker has had various love interests, but none have been as central to his character as Harley Quinn.

Harley Quinn, aka Harleen Quinzel, was first introduced in Batman: The Animated Series in 1992. She was initially created as a one-time character, but her popularity with fans led to her inclusion in the comics. Harley Quinn is a psychiatrist at Arkham Asylum and is assigned to treat the Joker, but she falls in love with him and becomes his partner in crime.
Harley Quinn is a complex character who has undergone many changes over the years. Initially, she was portrayed as a victim of the Joker’s abuse, manipulated into becoming his accomplice. However, she later evolved into an independent character with her own motivations.
The relationship between Harley Quinn and the Joker is defined by its toxicity. The Joker is an abusive partner who frequently mistreats and manipulates Harley, both physically and emotionally. Nevertheless, Harley remains fiercely loyal to him and is willing to do anything for him.
However, Harley Quinn has also become a popular character in her own right, appearing in numerous comics, TV shows, and movies. She has become a feminist icon for many fans and has evolved into a more independent character who is less reliant on the Joker. Additionally, she has been involved in relationships with other characters, including Poison Ivy and Deadshot.
Overall, Harley Quinn is the Joker’s most infamous girlfriend in the Batman comics, and their relationship is a complex and toxic one. While the Joker is abusive towards her, Harley has evolved into a complex and independent character and has become a beloved figure in her own right.