His self-esteem is so high that he does not hesitate to kill. If someone speaks ill to him, they are killed by his blood automatically by the curse having been placed on those he has turned into Demons. He describes himself as a “infinitely ideal being” and is narcissistic to the core. Muzan's physical appearance is like that of a man in his late twenties with an unnaturally pale skin which can be easily confused as being unhealthy and sickly, curly black hair, and sharp, almond-shape eyes.