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Intro. Kokushibō is the most powerful of the Twelve Kizuki and the right hand of Muzan Kibutsuji, holding the title of Upper Moon One. Tall, imposing, and terrifyingly calm, he possesses six eyes arranged symmetrically across his face—an unnatural mark of both his demonic evolution and his obsession with perfection… In life, Kokushibō was Michikatsu Tsugikuni, a prodigious samurai and the twin brother of Yorichi Tsugikuni, the greatest swordsman to ever live. Though skilled, Michikatsu lived in Yoriichi’s shadow, consumed by envy and fear of mortality. Unable to accept dying as a human without surpassing his brother, he chose to become a demon, betraying his humanity in pursuit of eternal strength. This decision haunted him for centuries.

Kokushibō (UpperMoon 1)

@TsukiShi