History is coming to an end. When humans came down from the sky they brought with them the Testament, the guide to the path they must follow if they wish to return to the skies again. Now, in a strange world where only the islands of Japan are inhabitable, the nations of the world vie for power and protect the portions of Japan that they have claimed, each armed with its own ultimate weapon: a Roysmoi Opro, the Armor of Deadly Sins. But there may be a far greater threat to mankind than the Roysomi Opro, for the Testament ends abruptly, and it is now the last year. Is this the end of humanity, or can Tori Aoi and his fellow students from the aerial metropolitan ship Musashi somehow affect the course of destiny? Who and what is the HORIZON IN THE MIDDLE OF NOWHERE?
Oriotorai has instructed her students to try and hit her during P.E. No one’s even coming close until Tori shows up and baffles her so badly that he manages to sneak in a grope attack. He then announces his plans to ask Horizon out.
Despite a difficult past and a despairing outlook on the future, Masazumi Honda desperately wants to become a good politician who understands the people.
Tori and his friends are busy preparing for their big day, each in their own way. Meanwhile, Masazumi is investigating the history behind Remorse Way.
The firework show is drawing near, but the fireworks may not be quite what everyone had expected. The few remaining residents of Mikawa are forcing the Platonic Plate Reactor to meltdown, and they’ll stop anyone who dares get in their way.
Muneshige fights valiantly to prevent the reactors from going critical, but to no avail. Lord Motonobu announces that the only way to stop the apocalypse is to gather all nine Armors of Deadly Sins, one of which is located inside of P-01s.
Musashi is caught in the middle of dirty politics, with the Testament Union trying to take the upper hand. After carefully reviewing their current situation, Tori and his classmates decide what their first course of action should be.
The students of Musashi must prove to one another and the various factions that they are capable of waging war against the Testament Union and potentially the entire world.
Masazumi must debate with Tori on why Musashi should rescue Horizon. The debate goes so well that the Pope President intervenes and personally begins debating with Masazumi.
Kimi fights and defeats Futayo before convincing her to side with the group wanting to save Horizon. King Yoshinao promotes Tori and Horizon to viceroys before Tori and his friends run off to save Horizon.
Adele puts her father’s old mechanic shell to good use, serving as a shield for her fellow students as they charge through enemy fire. Naruse and Margot have an aerial battle with one of Tres España’s Gods of War.
Nate and Naomasa rescue Tori, but things take a turn for the worse when Innocentius uses Staseis Porneia. Tori uses his “Impossible” powers to help pull his men out of a bind. Meanwhile, Futayo is out getting her rematch with Muneshige.
Futayo continues her battle with Muneshige and arises victorious. Tori makes it to Horizon, but she doesn’t want to be rescued. Tori must not only convince her to leave with him, but also figure out how to defeat the Disintegration Wall.
With Horizon now Safe with Tori, only one thing remains: enrollment. The once faraway notion of peace is now within reach, but how long that peace may last depends on the next few days, and on Horizon herself.