Luigi is the younger, less famous brother of Mario. He's very supportive of his older bro, and he's fully accepted his role as second banana in the realm of princess-saving, but things still never seem to go quite right for him.

Living in Mario's shadow seems to have given Luigi a bit of an inferiority complex. Mario's reputation as a high-jumping hero marginalizes Luigi's own qualities, even though Luigi is technically an even better jumper than his portly bro. The only things that spice up his otherwise lonely life are his secret love for Daisy and the... "unusual" attention that Waluigi seems to give him.