The story takes place in a time and space where ghosts are rampant and darkness engulfs the world. Day and night are no longer distinct, and the sky is always dark. Whenever night falls, all kinds of weird ghosts emerge from the darkness, threatening human survival. In order to resist the invasion of these ghosts, some powerful night watchmen were summoned. They have special abilities to compete with the ghosts, but becoming a night watchman also means being with the darkness for life and bearing a curse that will never be lifted.
