R5-K3 was an R5-series astromech droid who was owned by Vorn Tel-Ovis, the owner of a junk shop that was situated in the settlement Mos Shuuta on the planet Tatooine. Like most other R5 units, R5-K3 had a sullen demeanor, and it hated Tel-Ovis. During the Galactic Civil War, a band of fugitives, on the run from Hutt crime lord Teemo, came to Tel-Ovis' shop to acquire a hypermatter reactor igniter. R5-K3 did not alert Vorn that he had customers, leaving the old man to find out for himself.