In the magic world, at the Toristin School of Magic, young people learn magic courses here. Louise de la Valliere, a girl who has just entered the second grade, is nicknamed "Louise of Zero" because her spell casting success rate has always been 0. Every time she casts a spell, she fails, but causes an explosion, which messes up the normal study life of the school. This day is the magician's once-in-a-lifetime summoning ceremony for the familiar, and the summoned familiar will be with the magician forever. The other students successfully completed the summoning of the familiar, but as soon as Louise cast the spell, an explosion occurred without surprise. However, Louise still summoned a familiar - a human! The young talent from Tokyo unexpectedly came to the magic world and was treated as a familiar! The overwhelmed talent signed a contract with Louise, who did not treat the talent as a human. In this magic school, what will be the fate of the ordinary young talent from Tokyo?