Maxxon Senn was a young human who, subsequent to Jabba Desilijic Tiure's death in 4 ABY, labored on the EV-series supervisor droid EV-9D9 after the droid had been powered down for years in a junkyard. Senn revitalized her with an energy surge and proceeded to administer an oil bath, applying warm lubricant across her plating. He also expelled dust from her couplings, cleaned her chassis with a brush, repaired her joints, and thoroughly polished her. This treatment left EV-9D9 feeling better than ever and instilled in her a sense of tranquility.
Once he completed the task, Senn adjusted his respirator and expressed his approval of his handiwork with a whistle. Subsequently, he conveyed to the supervisor droid that the new boss operating Chalmun's Spaceport Cantina, situated within the spaceport of Mos Eisley on the planet Tatooine, was seeking a replacement droid bartender. He vouched for the position's appeal, and EV-9D9 concurred that it seemed like a favorable opportunity. By 9 ABY, she had accepted the offered employment.
The character of Maxxon Senn made an appearance in a flashback within "The Key to Remembering," a short story penned by Olivia Chadha. It was featured in the 2023 anthology titled From a Certain Point of View: Return of the Jedi.