Fill is Bill and Fay's son. He has his father's appearance with white fur and green eyes.
Fill is a bit more serious in tone than his fellow Star Fox friends but he's no less fun-loving. Much like the other members, Fill does not take betrayal lightly. He hates losing battles, especially to seemingly insignificant opponents. Their first defeat from Nefarious made him extremely angry with himself, because he had a chance to take a shot but did not. He has been known to display emotions of anger (which he often takes out on his friends), frustration, and becoming depressed. However, he's quick to apologize and states he just wants to protect his family.
He fights using a blaster.
Trivia:
Fill's name is a mix between his parents' names.
Fill is the son of a written-out character of the game he's in.