Takeru Yagi is a student at the private high school Izumo Academy. He doesn't have any relatives and is alone in the world. Fortunately he enjoys a happy life thanks to his best friend and rival Takeshi, and his childhood friends Kotono and Asuka. One day a tremendous earthquake strikes Izumo Academy and in a flashing moment, the entire school turns into an old, eerie ruin full of hideous monsters. Narrowly surviving, Takeru and Asuka find that all the teachers and students are gone. Even his best friends Takeshi and Kotono have disappeared along with the entire town. Then, strange people wearing ancient clothes emerge out of nowhere. What on earth has happened to the peaceful campus and town? Takeru hasn't the slightest idea that this is the beginning of a fantastic adventure he couldn't begin to imagine.—Discotek Media

Yagi Takeru is a student who goes to the Izumo Academy. He lost his parents when he was little, but he got adopted by Touma Rokusuke, who is like a grandfather to him. Takeru spends his days by getting kendo training from his grandfather and being with his friends like his kendo rival Yamato Takeshi, his childhood friend Shiratori Kotono and her sister Asuka. Because Takeshi isn't chosen as the representative for the kendo tournament, he takes it out on Kotono, but starts to argue with Takeru instead when Takeru and the others arrives. While they are arguing, mysterious light and woman appears which suddenly causes phase shifting and blinding blue light to be emitted from Takeshi hands then body while he screams in pain. Later they wake up scattered all through the school. The school is covered in vegetation and infested with insect monsters and the town is gone. After finding each other they gather in the schoolyard and while they are trying to figure things out, six big men in suspicious outfits appear and move towards them. They locate Takeshi and once again the mysterious woman appears. She uses teleportation magic to kidnap Takeshi and Kotono. Then armed men on horses appear and attack the suspicious men. What does the future hold for Takeru and the others in this strange world?

Takeru Yagi lives a normal, average life. He lives with his adoptive father Rokunosuke, and eats breakfast with two neighborhood girls, the sisters Asuka and Kotono. Takeru attends a kendo club at school with his best friend and rival Takeshi. It's an idyllic, peaceful life, where the greatest drama is whether Takeru or Takeshi will represent the school at the kendo tournament. Then one day, everything changes. Takeru and his friends are transported to a world like their own, yet fallen to ruin and filled with monsters. Moreover, people in strange clothes are highly interested in all of them.—Crunchyroll

Yagi Takeru has been living in the Touma family's house since his parents are gone. He was raised by Touma Rokunosuke, the head of the house. He is surrounded by many people such as Yamato Takeshi, his best friend-cum-rival from the kendo club, the Shiratori sisters, Kotono and Asuka, and his childhood friend, Oosu Seri. Life has been blissful until one day, an earthquake strikes the school and everything changes. Takeru awakens to find that the school looks as if it has been abandoned for centuries and reduced to ruins. He also realize that all the teachers and students have disappeared as well. He meets up with Seri and Asuka and they fled from the ruins, only to realize that the town they used to live in is completely empty. Subsequently, people wrapped in cloaks appear before him. They were told that they have been brought to another world.—Anime News Network