Nari is a 10-year-old millionaire boy exhibiting an egocentric personality, firmly convinced money resolves any predicament and habitually carrying 10,000-yen bills. He openly labels friends "poor" or "proletarian" due to their lower economic status. His most defining trait is an intense fixation on round objects, dictating lifestyle choices like inhabiting a circular mansion and fueling a distinct attraction to Koni's rotund physique. This obsession extends to avidly collecting spherical items.

He participates in chaotic adventures alongside Koni, High, and Moro, maintaining friendships despite condescending remarks about their finances. Speech patterns are described as effeminate or "fresa-like" (stereotypically upper-class) in certain dubs. Nari displays a passion for flying, occasionally referenced as "medio volador de Papantla," though the ability's specifics remain undefined.

Physically, he has pale skin, dark blue hair tied in a small ponytail, black eyes, and wears glasses. His typical attire includes a dark blue shirt layered over a green T-shirt, violet shorts, and black shoes.