Legend of Demon Realm

A young man with a strange origin and a peerless sword that has been passed down for thousands of years triggered a war that truly maintained the world. Here, there are not only humans, gods, gods, demons and ghosts, but what is even more terrifying is the human heart. As the young man continues to grow, he gradually sees everything clearly, but when he truly sees through the world, he realizes that the most complicated thing is actually the human world. One person and one sword, do they protect the heaven and earth or the soul? Is the demon world an alien world or a human world?