High-school girl Yuri all of a sudden finds herself on the rooftop of a high-rise building. She's trapped in an unusual globe surrounded by skyscrapers, where a concealed man cracked open a man's head with an axe before her eyes. Locating a method to endure this peculiar world, find her precious bro, as well as getaway becomes her top concern, yet she is beleaguered by risk not simply from the mysterious Masks, which have both vicious toughness and also viciousness, however other survivors transformed harsh or desparate by the insanity of the skyscraper world.