Become Emperor by Touching Bones

When I was five years old, my whole family was wiped out. The master said that it was the butler who did it. >Sixteen years later, I became a Level 10 Bone Changer, the only one in the world. >Until that night, I didn't know that the one who killed my whole family was the master who treated me like his own son. >What he wants is my pair of bones that can be used to replace the dragon's bones, to replace himself with a dragon's chair. >The closest person turns out to be the cruelest person.