Kex was the faithful droid of the bounty hunter, human/Zeltron hybrid, Abigaile Jade. He was named after a famous Mandalorian Crusader.
After the Battle of Toola, the droid accompanied her to the planet of Tatooine. When she was captured by the Arkanian smuggler Maka Jeth and his Yaka slave, Duwingo, Kex went to find Obi-Wan Kenobi. When it found him, it gave him information of what had gone on in his nephew's life.
When the nephew, Nathaniel Kenobi, came to Tatooine, he received Kex from Obi-Wan and left to find his wife and child on Wayland.