Summoners. An order of warriors who form blood pacts with patron beasts to summon as comanions in combat. When an amatuer named Thomas becomes a proffessional his dream of becoming an elite summoner under the service of his villiage chief seems ever closer and he'll do whatever it takes to make it. As a result Thomas, his sensei, and two friends Leo and Grey must face off against Harima a corrupt summoner working under Jose a dark summoner forming an organization to enslave all lands.