The Black Oni God of Darkness was the God and creator of all the Oni and the four gods. He wanted peace with the humans but Fortinbras wanted to rule and eat the humans and the Oni and let his Genma run experiments on them, so the Black Oni and his Oni solders lead the battle against the war hunger Genma and in the end the Black Oni almost destroyed Fortinbras, but he used all of his power. He swore he would return someday and save humanity from the Genma leaving Fortinbras almost with no power, he fell with his warriors and his four servants until he was reincarnated into Hideyasu Yūki.