The protagonist in 'incomparable demon king novel' might have a mysterious past. This past could be gradually revealed throughout the story, adding an element of intrigue. It could be related to how he became the demon king or what events led to his current position of power. His past experiences may also shape his actions and decisions in the present, making him a more well - rounded and interesting character.
He is probably highly intelligent. To be an incomparable demon king, he needs to outwit his enemies. His intelligence allows him to strategize and make calculated moves in different situations, whether it's in battles or in political intrigue within the story's world. Also, he may have a complex personality. He could be both feared and respected, with a sense of honor or a code of conduct that is unique to him, which adds depth to his character.