Kathy Kane is a superheroine who fought crime in the DC Universe as Batwoman. She first appeared in Detective Comics #233(1956).
A wealthy socialite with acrobatics training and an attraction to Batman, Kathy Kane modeled herself after him, taking the guise of Batwoman to both fight crime and win his heart.
The early years of Kathy Kane is largely unknown. When she first appears, she's a wealthy socialite who was inspired by Batman to fight crime. Using her skills as a former circus performer, she hoped that by helping the city as a new hero, Batwoman, she might not only make a difference but also hoped to start a relationship with Batman, whom she was smitten with. However, Batman was constantly concerned for her safety and would often urge her to retire from crime fighting. However, she refused to stop crime fighting, with her true identity known only to Betty Kane, her niece, who would later join her as Bat-Girl (originally because Betty blackmailed her, swearing that if she didn't get to be Bat-Girl, she would tell). Bat-Girl had feelings for Robin as Batwoman had feelings for Batman, so both worked as a team to both fight crime and woo the Dynamic Duo. After a few notable adventures, the two gave up on their life of crime fighting and Kathy decided to return to the circus.
Using her fortune, she founded the Kane Circus, which she managed and performed in without incident until she found herself caught between the Sensei and Ra's al Ghul, who were targeting her due to her connection with Batman. Soon, she was murdered by the League while Batman was fighting the Bronze Tiger. Following the events of the Crisis, a time warping event, her death and much of her past were erased from history and rewritten when reality was reset.
In the alternate reality of Earth-Two, a world where the exploits of the heroes from the 30's and 40's continued onwards, another Kathy Kane exists with a nearly identical history to Earth-One's Kathy Kane.