Hellhound (real name: "Kai") is a fictional supervillain from the DC comics 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 artifact 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". Catwoman scarred his face instead, deepening his already great hatred of her.
In the years that followed, Kai became a hired mercenary. Eventually he would get his wish and encounter Catwoman once more, coldly informing her that their master had been killed (although Catwoman is apparently unaware that Lady Shiva was the one to kill her sensei). Hellhound and Catwoman were forced to work together by an archaeological relic connoisseur named "the Collector," who wanted them to find him an artifact called "The Wheel of Plagues." Unfortunately, the Wheel was also being sought out by Ra's al Ghul, and Catwoman and Hellhound were forced into conflict with Bane. Bane bested them and took the Wheel, and Catwoman and Hellhound fought once again. Catwoman again bested Hellhound, leaving him alive even though he again asked for death.
He was later employed by "Jackie Pamerjanian," the drug kingpin of Rheelasia, to protect his crops. Hellhound was forced into conflict with another hero, this time Black Canary. She also defeated Hellhound, and Pamerjanian lost his drugs as the government raided the compound. Hellhound was last seen serving as Lew Moxon's bodyguard at the meeting of Gotham gang bosses before the "War Games." He was unable to save his boss from death at the hands of Philo Zeiss, who killed Kai in the process.
Powers and Abilities
Kai is an accomplished martial artist, and a competent attack dog trainer.
In other media
Hellhound appears in the DC animated film Batman: Bad Blood. He appears as one of Talia al Ghul's henchmen part of a team consisting with other Batman villains.