After death, the souls of people will return to the underworld, but there are always some souls that cannot enter reincarnation due to unresolved obsessions. Over time, the souls have turned into ghosts. When the underworld is in distress, a man appears.
"I can help you catch the devil"
"You are?"
"Referring to the successor of the soul master——Rui."
Concept: A fox saves an emotionally numb soul master