Known as an exceptionally cowardly person afraid of death by Tamayo, Kibutsuji Muzan had a great obsession with immortality.
This demon's progenitor was born in the distant Heian period, and before his birth, his heartbeat had stopped while in his mother's womb, being born into the world as a stillborn. Ultimately though, he survived, but he was diagnosed with a terminal illness that confined him to bed, proclaiming he wouldn't live past 20.
He should have died a very, very long time ago.
However, a doctor, in an attempt to prolong his life, formulated a medicine that changed Kibutsuji Muzan's entire life.
Yes, Kibutsuji Muzan was originally a mortal human susceptible to sickness and death.
It was not until he consumed the medicine from that doctor that Kibutsuji Muzan underwent a transformation, not only regaining his health but also gaining immortal and formidable strength.
From that moment, a new monster appeared in the world—a demon.
