Tian Long was an orphan. While living in misery, Tian Long found a Death Note that would kill his only enemy, who was responsible for his misery.
He was able to cross the worlds with his Death Note after a series planning and actions. He has no attachments to Earth. He doesn't have a great sense of justice.
He just follows his heart and does what he believes is right. Follow Tian Long on his quest to become the Divine Emperor Of Death in the Cultivation World.