Kyoukaisen-jou no Horizon  

Horizon in the Middle of Nowhere, Horizon on the Middle of Nowhere, Горизонт на границе пустоты, Горизонт посреди пустоты, Хоризонт по средата на нищото, افقی در ناکجاآباد, افقی در وسط هیچ کجا

In a distant future, humanity has abandoned Earth due to its devastation. They then journeyed into outer space but were hindered by an unknown phenomenon that prevented them from traveling further. As a result, they returned to Earth and discovered it uninhabitable except for Japan. To accommodate the entire human population, pocket dimensions were created around Japan to house everyone. In order to find a way back to outer space, humans began reenacting their history according to the Holy book Testament. However, in 1413 of the Testament Era, the nations from the pocket dimensions invaded and conquered Japan, dividing it into feudal fiefdoms and forcing the original inhabitants of Japan to flee. The refugees now reside on the city ship Musashi, which constantly travels around Japan while being monitored by the Testament Union, the authority responsible for re-enacting history. Rumors of an apocalypse and war have started spreading when the Testament stopped revealing what would happen after 1648. Taking advantage of this situation, Toori Aoi, head of Musashi Ariadust Academy's Supreme Federation and President of the student council, leads his classmates to seize this opportunity to reclaim their homeland.