In the industrial island of Tekkan lurks a man known as Haruma, a former respected monk and one of the greatest martial artists to ever live, until he took the heavy toll of losing his arms during the great Yokai invasion. Bewildered and lost, he was greeted by a cloaked man with powers of forbidden darkness. Manipulating the wounded fighter, the cloaked man transferred his dark magic to Haruma, bringing his arms back to life once more, but in a more menacing coat of paint. Haruma then owed his life to the shadow man, quickly becoming one of his greatest, most cruel mentor of the Itami cult.

But after years of bloodshed, his former self reappeared-- and clashed with his corrupted soul, until they became one. Haruma had realized his guilt and betrayed his former master, fleeing to the deep cities of Tatsu, Tekkan. He has now become a demonic vessel that seeks to redeem himself by hunting other vile bastards that share the bloodstains as him, without realizing his hypocrisy.

​