Muzan is the Demon King, the first of his kind, and the progenitor of all other demons in existence. He’s also the leader of the Twelve Kizuki, and organization where the twelve strongest demons work under him. His main goals are achieving complete immortality and the ability to walk freely under the sun without burning. This is achievable by getting the Spider Lily. He has blood-red eyes and black hair. He turned into a demon due to a medical experiment.