Waluigi

From Waluigiwiki

Waluigi is the mascot of Nintendo and brother of Wario. He is tall and scrawny. He is cousin of Mario and Luigi. Deliberately created to be a selectable character in various multiplayer games, Waluigi made his debut in Mario Tennis and has been making regular appearances in Mario Party and spin-off titles ever since. He has been playable in several games to date, although none of them can be classified as mainstream adventures in the Mario series. He has been voiced by Charles Martinet ever since his first appearance. The details of Waluigi's past are unclear, as he is an extremely undeveloped character with no confirmed back story. Waluigi simply appeared in the Marioverse as an apparently long-time resident with no explanation regarding his background. Waluigi has evidently been antagonizing Mario and, more so, his brother, for quite some time, even before his debut. He is confirmed to be the same age as Luigi and it was clear from the opening movie intro in Mario Tennis that he and Luigi have been at odds before.