Minako and Minato are twin siblings who return to their home city 10 years after departing it, entering a life that was never familiar to begin with, but one that would continue to grow more distorted and dangerous as the days pass.
They come to learn that ever since a disastrous occurrence in that same city, the world was forever changed. Now, a secret time between the day and night exists, one when humanity is snuffed out into coffins and distorted monstrous creatures roam the streets.
As the pillars that form the foundation of their world begin to buckle and crack, the twins learn that they are two of the few who can save the world, and they find themselves teaming up with unlikely allies to find a way to restore the world to its rightful balance. However, as they struggle to survive in this new life, fear, distrust and doubt begins to spread between them and their allies, and even among themselves.
Just what caused the rift in the world through which time itself distorts, and what kind of terror awaits the unassuming twins...?