Hellhound (true name "Kai") is a fictional supervillain from DC and an enemy of the on-and-off supervillain Catwoman.
Kai was the best student in the Armless Master's dojo in Gotham City. Kai was also a thief, which brought him into conflict with a young Selina Kyle, who "tainted" a religious ceremony he was performing by touching a religious artefact depicting Bast that he had intended to steal himself. After Kai severely beat her for her interference, Kyle followed Kai back to the secret dojo, where the Armless Master welcomed her as a student. She began studying, and quickly showed Kai up in front of his master. Kai soon learned that Selina had taken on the identity of Catwoman, and, in religious zeal, took it as a sign. Adopting the identity of Hellhound he attempted to force Selina to kill him, believing this would finish the ceremony she had interrupted when they first met, and that he would be reborn as a "true hound of hell".