Professor Einstein, who had always regretted the fact that the atomic bomb was born from his own discovery, placed his wish for the future into the hands of two boys, Hikaru and Haruhi. Then it happened in 2005, Tokyo. A mysterious young man appears before Ruika, a girl who lives as a dead brother for her mother. He is Hikaru, who took a tablet to stop his growth in order to find the girl who holds the key to saving the world... Past, present, and future... A spectacular historical fantasy that transcends time and space!