In the springtime, when a child reaches adulthood at age of 15, they undergo a ceremony at a temple to receive their skills. Zesh is born into a noble family whose influence is slowly waning. He is discovered to have multiple skills, a rarity in the world, but he is kicked out of his home when he fails to receive the combat skills his family craves. The skill he has acquired, the Master Key, is a skill that allows him to fit his key into any keyhole…!