2015…
Many had remember it as the Judgement Day. At that particular time, the humanity had been attacked by an unknown creature called Vertex. They are indiscriminately kill every single human they passed by. All conventional weapons are useless against them, even a nuclear blast didn't do much to them. There's nothing human can do, as if it was a punishment sent directly by the God. People have no choice but run and hide, or so they though.
In the same year, it said that several young maiden have awaken their divine power as they gain a weapon that is able to defeat those creatures. Furthermore, when there are Gods who wished to eradicate humanity, there's other Gods that want to protect them, so they have created a "safe" place protected by divine power so Vertex won't be easily to invade the place. Under the direction of the divine, all those maidens and peoples who are survive until now gathered to that place, which known as Shikoku.
Meanwhile, those maidens, whenever they're gathering on the Shikoku or stay at their homeland and protect them, have been called Yuusha (Hero) by people and the organization who said have directly given command by the Gods who are pro with humanity, later will called "Shinju" and the organization called themselves "Taisha". Those Yuusha will trained and soon, they will be ready to protect humanity, until the time they can reclaim what they have lost.
Or so they though…
As many have focused on those Yuusha, several have witnessed another miracle that happen in front of them. Those who tried to survive on the land have reported and witnessing a figure, clad in black armor was saving peoples from those Vertexes, even before the so called Yuusha is ever appeared. Many lives had been saved by this mysterious figure in black armor and yet no one can learned its identity. However, many has refer that figure as Kyuuseishu (Savior), which some say have a same standing as the Yuusha.
Taisha, learned the Kyuuseishu existence, try to invite this figure to help them protect people in Shikoku with the Yuusha. However, they never have any chance to do it so as everytime he save people, he suddenly vanish afterward. It can't be help that no one know the savior's identity, aside from the fact that he is a male. Many has try to learn more about him, but come home empty handed. And so, the Kyuuseishu still remains mystery. Whatever he is real or not, no one know aside those who have seen him.
And thus, this is a story of post-apocalyptic world from the Kyuuseishu view and Yuusha view. And the new page have been opened…