After leaving his job as the best assassin in the world, this french man by the name of Paul Verlaine, an artificially made human who can control gravity, has run off to the Japanese countryside with his best friend Rimbaud, to take care of his little brother, another artificially made human with the same powers as him, by the name of Nakahara Chuuya. Verlaine and Rimbaud have a pretty complicated love-hate relationship, but Verlaine loves his little brother Chuuya more than anything.