EV-A4-D, commonly known as A4-D was General Grievous' caretaker and medic droid, who's job was to work on the general's cyborg body and repair him when he got damaged. He had sadistic personality due to a programming defect.
Lair of Grievous
When Jedi Master Kit Fisto and his padawan Nahdar Vebb infiltrated Grievous' lair and sliced of the cyborg's legs, Grievous summoned EV-A4-D to repair him. The droid was thoroughly upset that he had to do this work when he had other things to do, and was quite disrespectful with his master while repairing him. Later, when Grievous attacked the Jedi once again, A4-D watched his duel with Nahdar Vebb on a camera, and cheered for Grievous while watching the fight. He was quite comfortable until he realized that one of the Jedi was missing, and anxiously wondered where he could be. As an answer to his thought, Kit Fisto entered the room and beheaded the sadistic droid from the behind.
- Lair of Grievous (First appearance)