The Familiar of Zero (Light Novel) #1 - Zero's Familiar

Louise is known as Zero due to her inability to correctly use spells but somehow manages to summon her familiar. It’s a common ceremony that everyone in the 2 year of Tristain Academy participates in. Everyone is amazed that she manages to summon a lowly human commoner named Saito. Together Louise and Saito start their interesting master-familiar relationships and causes lots of trouble for Louise.