Action, Shounen, Sci-Fi, One Shot

In a secret laboratory, a group of scientists, disregarding ethical concerns and acting without authorization, cloned and altered the cells of an adult male. They hope to turn the artificial person into a half-machine superweapon. After the group of illegal scientists got arrested, somehow the superhuman weapon had disappeared. The story is about the life of the miserable yet dangerous weapon under the figure of a boy named Buya.