Did an eighteen-year-old boy die for no reason because the King of Hell was old and couldn't see clearly, and marked the wrong name in the Book of Life and Death?
A fifteen-year-old girl's life is full of curiosity and optimism.
How will their story end?
"Then become a guardian ghost. When the person you're protecting turns eighteen, bring her to the Underworld, and she'll take you away. How does that sound?"
"I guess that's the only way."
Theme: The Underworld isn't scary. It might even be a little funny.