Although the majority of the characters in Kimetsu no Yaiba are demons, it’s not surprising that if you watch how they act, it’s not surprising that they are hated by the fandom. They are not adjacent to any moral standards and are completely corrupt in character.
Akaza mocks those he considers weak and vulnerable, including the Flame of Hashira. Kizuki’s ambition to become the strongest has pushed him into many conflicts with his superiors, but it is Akaza’s lack of knowledge and bravery that make him an extremely impressive character.
After losing to Kyojuro Rengoku, he ran away and hid in the darkest place, much to Tanjiro’s anger. However, Akaza’s attempt at atonement before he died made the audience see him in a different way.
The only reason why Zenitsu isn’t hated by the audience is because he’s not a demon, doesn’t kill, and doesn’t eat humans.
Except for this feature, Zenitsu is overall a bit out of place in the story, especially when he’s interested in Nezuko, Tanjiro’s younger sister. He can be manipulated, but the truth is that Zenitsu is quite cowardly, mean, and often overreacts to problems.
Kyogai’s status was stripped by Muzan, so he spent his life hunting and devouring “marechi” to increase his power. Although he maintains a rigid demeanor, he does not act in the same violent way as his opponents. However, because of the desire to be noticed by Muzan, Kyogai committed many terrible acts such as killing innocent children. Therefore, later on, he was no different from his own kind.
Rui’s introduction made the audience stir, but he was not as savage as many of the other members of the Twelve Demon Moons. But this does not make Rui different. On the contrary, he enjoys watching his prey fight and gradually succumb to his power.
Rui longs for a family that loves him, but in an ironic and heartbreaking way when he projects hatred on his human opponents.
Enmu’s enthusiasm for inflicting violence on his victims infuriates the audience, more so when viewers notice that he tortures his minions in exchange for better dreams. .
Enmu rarely cared about his fellow demons, even enjoying their deaths. Enmu enjoys the sufferings of his fellow humans, so the audience understands for himself that he wishes to perpetuate the pain and misery of all living beings around him.