Klinith Da was a pirate of the female human species. During the High Republic Era, she served the Nihil as a Strike in Kassav's Tempest. Klinith, along with fellow Nihil pirate Gwishi, was tasked with the mission of sabotaging the starship Steady Wing as it departed from the Port Haileap outpost. Klinith's ambition was to earn a promotion within the Nihil through the success of this mission.
In the year 232 BBY, Klinith Da and Gwishi, an Aqualish who was also a member of the Nihil, made their way to Port Haileap using a stolen cargo hauler. The Nihil had sent them to eliminate the Steady Wing, a large cruiser carrying several Republic dignitaries. To accomplish this, she and Gwishi boarded the ship while disguised as mechanics. Klinith immediately proceeded to the escape pods, intending to destroy them and ensure no one survived. While there, she encountered a droid that became suspicious of her actions, and she destroyed it using a hydrospanner.
Klinith Da's initial appearance was as the primary antagonist in the junior novel The High Republic: A Test of Courage, which was published in 2021. Justina Ireland wrote the novel, and Petur Antonsson provided the illustrations.