Seto was raised under the watchful eye of an his grandfather, who took the role of both parent and teacher. The child spent his young life sheltered within an old house, while his grandfather took the dangerous job of scouring the hostile land for supplies. Whenever the old man was at home, he tried to teach the boy all that he knew. The man focused especially survival skills, the dangers of the night, and on how to battle spirits through the power of art made possible from a magic stone. However, teaching was a constant challenge. The boy had trouble focusing, and would daydream in the middle of his studies. The one thing, the boy always paid attention to, the grandfather discovered, were the few stray cats that would occasionally sneak their way in on rainy days. Upon the discovery, the old man, in one way or another, incorporated cats into his teachings so the boy would paid attention. Tragedy struck when Seto was ten years old; his grandfather had passed away in his sleep. After the boy buried his only family member, he stowed away within the house, with the stray cats to keep him company. Days went by, before he was forced to leave. There was little to no supplies, and the boy had grown terribly lonely that even the company of cats could not quench his thirst for human companionship. With a goal in mind, the child had set off to find other humans in treacherous abandoned world, filled with vengeful ghosts.