Shuusengo no Scarlet

A former kamikaze pilot named Kadode works at a construction site in Tokyo, a place he refers to as the resting ground of his fallen friends. He learns about a reward for locating an object called "Scarlet," which is revealed to be a third atomic bomb the U.S. military nearly deployed at the end of the Pacific War. A struggle over this bomb begins, centering on survival in the aftermath of the war and nuclear threats.