The Ultimate Little Ghost Officer

This novel is all about hilarious adventures. If it doesn't make you laugh, I'll take full responsibility. Don't read while eating, or you might spit out your food. And don't read on the toilet either. You're responsible for any consequences! I accidentally became a ghost officer, only to find myself caught up in an earth-shattering scam. The underworld? It doesn't exist! Ghosts? They don't exist either! There were never any ghosts in this world. The only thing that exists is the evil in people's hearts. As the mist clears, caught between the greater good of the nation and love for my homeland, what path should I take?