Louise Francoise Le Blanca Dela Valliere is the main female protagonist of Zero no Tsukaima anime and light novels.
Louise is the third daughter of the Vallière family, an aristocratic family well known in Tristain. She is currently attending classes in the Tristain Academy of Magic, where she is known as Louise the Zero due to her zero success rate at spell casting and lack of any elemental affinities, a nickname acquired even before the first episode.
Louise is married to Saito Hiiraga.
In the AWA fics, Louise is a student at the AWA Academy and is part of Class 5.
In the XP4 fics, Louise is part of the Heroes Coalitions and is a member of the Pact. She also attends the Vanguard Academy as a student.
Louise is a petite girl with long, pink hair and pink eyes. She is usually seen in her school uniform, which consists of a white, buttoned up shirt, a short, black skirt, and a long, black cape. She has the school's emblem tied onto the collar of her shirt. She also wears long, black socks that goes up to her thighs and a pair of black shoes.
As a Noble, Louise defends her honor as a benevolent and "superior" person, like other Nobles. She states that is her responsibility as a noble, to make sure her highness the princess is safe and that her familiar's well being. Louise is a very stubborn girl. But, as Henrietta mentions, her heart is pure. Louise is also very persistent which is shown when Kirche von Alhalt Zerbst bullies her. She endures it strongly and pursues her goals to prove that she is not a zero.
Her poor magical ability is due to her alignment to void magic, an ancient branch of magic which only four people can currently use, with the the last known user before them being Brimir; because of the branch's rarity the Academy does not have the ability to properly train Louise in its use, unlike other students who can learn their magical specialization from teachers who share their alignment. Void magic itself seems to be mostly capable of only destruction; any time she tries to use it for anything else it will result in an explosion of varying magnitude. She has been known - however - to be able to do relatively simple spells, but her use of void magic requires a certain amount of time to build up before use.
- Louise is the first character from Zero no Tsukaima to be introduced in the AWA fics.