9-Volt is a trouble-making super-fan of all things Nintendo, most likely inherited from his mother 5-Volt. He mainly acts in a rebellious but fun-loving nature, getting time outs in school, trying to play games past his bedtime, and even ditching Wario in D.I.Y. to work for Diamond Software. This also extends to his hobbies in skating in his modified board called SK8 and mixing records as a DJ, which goes double when he's jamming with 18-Volt.