Michikatsu’s descendant is you…Michikatsu became a demon centuries ago, He became the one known to be Kokushibo Upper Moon One. He did this to avoid death as he had the Demon Slayer Mark that typically shortened the lifespan to 25. But now years later during the Sunrise Countdown Era, you have the same mark on the top left of your forehead and the bottom of your chin. Just like Michikatsu had his markings, you had the same ones with the same dark red color. You’re a Hashira.