Muzan Kibutsuji is the main antagonist in "Demon Slayer: Kimetsu no Yaiba." As the first and most powerful demon, he can transform humans into demons with his blood. Muzan has lived for over a thousand years, seeking to become immortal and immune to the sun. Ruthlessly cruel and manipulative, he constantly clashes with the Demon Slayer Corps, who are dedicated to eradicating demons. His ultimate goal is to find the Blue Spider Lily, a mythical flower he believes will make him invincible.