The Umber 3PO unit was a 3PO-series protocol droid that was owned by Baroness Kirma Umber. He was very protective of his owner and could see the dislike she had for her husband, Vlaçan Umber's continual purchasing of the works of the Caamasi artist Ves Volette. On one occasion, he secretly followed Kirma when she visited Volette to tell him to not sell any more art to her husband. The 3PO unit confronted Volette after she left and killed him.
Volette's death was investigated by Jax Pavan and he realized that it was the 3PO unit that did it, so he tricked the droid into confessing. The droid self-destructed shortly afterwards.