Walter

Walter is fiercely loyal, dignified, patient, and protective of Rill. He treats people who genuinely befriend his master warmly but can become threatening toward anyone he thinks may harm him.

His loyalty is not passive obedience. When Rill's uncontrolled Painting Magic destroys his surroundings and leaves Walter badly injured, Walter responds by slapping him and explaining that other people cannot understand his art if Rill never tries to understand them.

That willingness to confront Rill becomes one of the most important influences on the young mage's development. Walter does not want to suppress Rill's creativity; he wants him to bring it into a world shared with other people.

Walter is a Magic Knight and carries a grimoire, but the series does not establish his magic attribute or named spells.

His most clearly demonstrated physical ability is surprising speed. Asta notices that Walter can move far more quickly than his age and appearance suggest.

Walter's usefulness is therefore portrayed less through battle and more through experience, observation, and his ability to keep Rill focused enough to function as a Magic Knight captain.

Walter is assigned to care for Rill during the nobleman's childhood. Rill's obsession with painting becomes increasingly destructive after he receives his grimoire and shuts himself away from other people.

After being injured by Rill's uncontrolled magic, Walter forces him to recognize that artistic communication requires understanding the people who see his work. He suggests joining the Magic Knights, where strong opponents can provide limitless inspiration.

Four years later, Walter attends the Magic Knights Entrance Exam alongside the now-captain Rill.

He later accompanies Rill to the Royal Knights Selection Exam, offers Asta tea after learning that he has befriended Rill, and watches the captain's matches while explaining his behavior to others.

Rill Boismortier is Walter's master, close companion, and the person to whom most of his life is devoted. Walter's intervention during Rill's childhood directly influences him to join the Magic Knights.

Asta earns Walter's gratitude because Rill considers him a friend. Walter responds by welcoming Asta with tea during the Royal Knights Selection Exam.

Yuno becomes an opponent Walter watches carefully during the tournament, particularly after Spirit Dive raises the danger facing Rill.