Katherine "Kate" Kane is a Gotham City socialite and a distant cousin of Bruce Wayne. At some point prior to Scarecrow's attack on Gotham, Katherine tried to contact Bruce in regards to a party celebrating her engagement to Maggie Sawyer. She voiced concern over Bruce's lack of public appearances over the previous months, and remarked that it was he who taught her the "importance of keeping up appearances".
- In the comics, Kate Kane is a masked vigilante known as Batwoman, inspired by the activities of Batman, despite not working alongside him. In Arkham Knight, it is not directly stated whether or not she operates as Batwoman.