The great “disaster” that attacks Tokyo on the night of meteor showers. Humans were powerless before the huge “it” that suddenly flew. An urban area that is drowned. The earth that is stained with fresh blood. Mankind to forgive the flaws until they are perfect. The boy, Sugawara Steel, who was deprived of his childhood friend by “it” was only despairing. When you are guided by a mysterious edge and grab the “sword” of tradition, your subtle hope will be restored. That is the "dragon" killing sword, "Sakumo no Sword". The old legend is revived. Boy, go beyond the myth!