Jean Genio is an evil genie who was trapped inside a sealed bottle for ten thousand years before being accidentally freed by Pac-Man. She is a tall, vaguely humanoid figure with lilac or pink skin and platinum blonde hair, which she often wears in a ponytail held by a gold beaded band. In keeping with her nature as a genie, she has no legs, possessing instead a ghostly tail that allows her to float everywhere she goes. Her attire consists of exotic garments, including a red crop top, adorned with a wide assortment of golden jewelry such as bands and a pair of large golden earrings that complement her notably large ears.

Despite being over ten millennia old, Jean has the personality of a maliciously spoiled child. She is immature, arrogant, and bratty, with a sassy demeanor reminiscent of a teenager, often shifting her head from side to side. Jean finds genuine amusement in tormenting and pranking others, using her vast powers to cause massive devastation without an ounce of concern for the harm her evil mischief inflicts. Even those who become her masters are not exempt from her cruelty, as she will happily twist their wishes and find creative ways to make them miserable whenever she can get away with it. Her voice has a somewhat nasal quality, and she punctuates her laughter with snorting sounds.

Jean's primary motivation is her own selfish amusement and a desire for chaos. She delights in showing off her magical abilities and bragging about her age, viewing the world and its inhabitants as playthings for her entertainment. Her role in the story is that of a powerful antagonist who, upon being released, immediately attempts to take over Pac-World, forcing Pac-Man to confront the consequences of freeing her. She displays a particular flair for dramatic twists of fate, and one of her notable nicknames for Pac-Man is Pac-Master.

In terms of notable abilities, Jean is a powerful magic user capable of granting wishes, though she almost always corrupts the intent behind them for her own amusement or to cause suffering. She can perform magic by snapping her fingers, which produces a distinct ding sound, and her simple gestures can cause widespread destruction. As a genie, she possesses an effectively immortal lifespan, having existed for over ten thousand years without apparent aging. Her floating, legless form allows for effortless navigation of any environment, and her overall design sets her apart as one of the few characters on Pac-World with a standard humanoid form rather than the spherical shape typical of Pac-People.