Louis is a tall young man with pale skin, blond hair trimmed sideways and blue eyes. He wears the standard Appleton Academy uniform.
Louis is an arrogant and malicious young man. He feels great pride in being the son of the minister of defense, hoping that everyone will respect him just for that. He is greatly influenced by his father, sharing all his opinions about the need for violent politics as well as his contempt for witches. He has quite the propensity for cheating, using all kinds of tricks in order to overcome others in simple card games or serious duels.
After being saved from Pixels-possessed armor, Louis finally realized errors and harm he done both to himself and others. His opinions about witches seemed to improved to the point of him being neutral towards them at best, as he now willing to support Akko and her friends in stopping Noir Missile.
Louis appears at Appleton Academy with his father, showing in complete agreement with everything he says about politics. When Amanda collides with, Louis was upset that this does not know who is also leading to a "mouse" that are banned in the academy for his relationship with witches, causing a fight between the two that is avoided by Andrew. Later, Louis was playing cards with some of his classmates, when Amanda intervenes revealing he was using a mirror to cheat. When Amanda reveals her identity without knowing that she was unable to use magic, Louis orders the capture and take her to the basement where they would be punished along Akko. However, Andrew returns to intervene by pointing out that all conflicts in the academy must be resolved with a sword duel. While at first Louis has the advantage in the duel, Amanda is the one who ends up winning. Even so, Louis breaks the Holy Grail by releasing the Pixels that Croix had concealed in it, which possesses an armor that takes Louis as a captive. However, Amanda manages to rescue him and then he admits his mistakes to his father.
Louis is seen next to the other students of Appleton watching Akko and her friends chasing Noir Missile on one of his friends' computer and wondering whether they're trying to catch up the missile. Convinced that they indeed trying to stop the great threat, he and his friends gives them their Fuel Spirit.
Louis is jealous of Andrew, and considers him a rival. The two are constantly in disagreements where he more than often left seething with fury every time Andrew rightfully pointed out his biased views and opinions (especially when it comes about witches and those who happened to be part of seemingly outdated magic community) as shown in Keisuke Satō manga. Even so, he willingly accepts Andrew's request of a one-on-one battle between him and Amanda instead of execution when they discovered Luna Nova's resident troublemaker and Akko being not only witches, but also infiltrated their academy for their fabled Holy Grail.
Louis hated Amanda for being a witch and insolent. But after their duel, his frustration makes him break the Holy Grail, releasing the Magitronic Armor. Amanda saves him, making him realize witches are not bad people, and beholden to her.
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