Dragon Pet Store! My Universal Domination Pet

Aston runs a dragon pet store, where every species of dragons is sold to communers—a set of people who can train dragons to battle and use them for various daily tasks, including domination of various areas. The dragons come with different skills, ranking from D class - S class. But Aston had never tamed a dragon, despite running a store for them. All because he lacks a malo core, which help communers tame and link with their dragons. One day, he arrived at the store and saw a blood-red dragon lying on his reception table, whistling to melodies. Dragons don't do that! It said, in a joyous tone: "Hey, Aston! I have a deal you would love to know about. Are you in!?" ________ Happy Halloween!