A beast tamer without a familiar, Lock had been supporting his friends in an S-Rank party until they finally decided to use him as a decoy and abandoned him. After a conversation with the Fenrir that his party was attacking, it chose to serve Lock as his familiar. By using and expanding the "Mini Monster Garden," Lock gathers more and more familiars to form the strongest—and cutest—party ever. A fantasy where men and beasts go on adventures together.