Kaah Ohtok served as the Padawan to the Jedi Master known as Lonna Vash.
Initially, both Kaah and Master Vash were intended to cross paths with the Jedi Exile on the world of M4-78, but this plot point was ultimately removed from Star Wars: Knights of the Old Republic II: The Sith Lords.
Game files indicate that Kaah and Vash had fostered a Force bond during Kaah's training. This bond suffered damage when they were separated while fighting to liberate M4-78 from Sith control. Losing his connection to Vash, he mistakenly believed her to be deceased, which fueled his desire for vengeance and a misguided mission to stop any Sith from reclaiming M4-78.
While the Exile explored sections of M4-78, Kaah adopted the persona of ES-05, the planet's environmental Archon, and falsely accused the Exile of being a Sith Lord. Unwilling to heed anything the Exile said, Kaah dispatched numerous waves of droids to attack her, aiming to prevent what he perceived as the onset of another Sith occupation.
Ultimately, the Exile was to confront Kaah, at which point his true identity as Vash's apprentice would be uncovered. The Exile then had the choice of aiding him in returning to the light side, eliminating him, or pushing him to the brink where he would take his own life.
The excised content provided no clues as to Kaah's species, leading to common assumptions that he was either a Human or a Twi'lek.