Although she studies at Tristain Academy, a prestigious school for magicians, she has a major problem: Louise is unable to cast magic properly, earning her the nickname of "Louise the Zero" from her classmates. When the first year students are required to perform a summoning ritual, Louise's summoning results in a catastrophic explosion! Everyone deems this to be yet another failure, but when the smoke clears, a boy named Saito Hiraga appears. Now Louise's familiar, Saito is treated as a slave, forced to clean her clothes and eat off the ground. But when an unfamiliar brand is found etched on Saito's hand from the summoning ritual, it is believed to be the mark of a powerful familiar named Gandalfr.

Media Factory published 20 volumes between June and February The series was left unfinished due to the author's death in , but was later concluded in two volumes released in February and February with a different author, making use of notes left behind by Yamaguchi. The story features several characters from the second year class of a magic academy in a fictional magical world with the main characters being the inept mage Louise and her familiar from Earth, Saito Hiraga.

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 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.