Koval Renge was a Sith Lord of the male persuasion, either a Human or a Sith pureblood, who was in the service of the Sith Emperor of the reconstituted Empire as his Sith Executioner.
Renge used his ceremonial executioner's blade to kill hundreds of those who opposed his master, but he eventually became afraid of the Emperor's strength and attempted to double-cross him. The Emperor then used Renge's own weapon against him, shattering the sword and embedding a piece of it in Renge's torso. After his injuries recovered, Renge, with the fragment still inside him, was thrown into the bottom of the Dark Temple on the planet Dromund Kaas.
Koval Renge's character was developed for Star Wars: The Old Republic, a video game by BioWare that came out in 2011. He is referenced in the Codex entry about the Blade of the Sith Executioner. This entry, along with "Lord Parnax's Lost Recordings" and "The Phobis Devices," were originally planned to be discoverable within the Dark Temple. However, they were cut from the final release of the game, although the Codex entries remain in the game's data and contribute to the total number of Lore entries listed for Dromund Kaas.