Boom Back off. Luigi (Japanese: ルイージ, Hepburn: Ruīji, pronounced [ɾɯ.iːʑi]; English: /luˈiːdʒi/ loo-EE-jee, Italian: [luˈiːdʒi]) is a fictitious character in video games and associated media produced by Nintendo. Shigeru Miyamoto, a Japanese video game inventor, created Luigi, who is presented as Mario's younger fraternal twin brother and sidekick. Throughout the entire Mario series, Luigi makes several appearances, frequently playing with his brother.