This world possesses a dual nature, the Inner Realm and the Outer Realm. Within the Inner Realm, creatures feed on the living, while in the Outer Realm, people lead peaceful lives under the warmth of the sun. Unbeknownst to anyone, on an ordinary day, two worlds that were once destined to remain forever apart begin to merge. Ordinary individuals suddenly find themselves facing horrifying monsters, disrupting their once-serene lives. But never succumb to fear, for the Nocturnal Guardians rise to obliterate any creatures that menace humanity. They dedicate themselves fully, even sacrificing their own lives, to preserve the world's harmony. Superpowers no longer serve as tools to disrupt societal stability or oppress the common folk; instead, they have become the sole chance for saving the world. If darkness is poised to engulf everything, the Nocturnal Guardians will stand before all regular humans, their blades pointed at the abyss, ready to wage war against it.