A man has to go back in time to fix a specific failure that caused by humanity.

2 high-school students battling for the first prize in a scientific competition that was organized by the government for some suspicious purpose, but the result was seemigly determined by coincidence.

An ordinary day of high-school students, in this extremely beautiful world.

The story of 2 people that have been friends for multiple lives, while one of them is on a mission to save the nation. In order to succeed, both of them have to revisit their old memories of their past lives.