Returning to the Mortal World with a Ghost Constable

After a college student dies in a car accident, his soul falls in love with the ghostly escort guiding him to the Underworld. After surviving countless dangers together, the two finally return to the world of the living. They think they can settle down and live normal lives, but their unauthorized return has upset the balance between yin and yang. Countless ghosts slip into the living world through the boundary they opened, leaving the two caught in a terrible dilemma...