Waluigi

Waluigi is a fictional character in the Mario series of video games. As Wario is Mario's rival, Waluigi's rival is Luigi. His relationship to Wario is foggy, at best, it his highly likely that he is Wario's younger brother, and one of his few friends. Its also worth noting that he seems to have a thing for Pirhana Plants, as seen in Mario Party 3.