What happens when a class from a modern day high school are inadvertently transported to the to one of the bloodiest eras in Japanese history?

Individuals from the spirit realm who simply wish to have fun in the human world and a human who wishes they would just leave him alone must survive in a world of constant civil war. They will eventually become embroiled in a much larger conspiracy that may change the future of Japan permanently. 

Nakanu nara

FairyTaleofDoom overlord_hupp darkanime13