Webkokushibo lived for more than 400 years (image via shueisha) kokushibo lived from the sengoku era to taisho era and became the oldest demon in the 12. Webthe history of kokushibo from demon slayer: Kimetsu no yaiba, the tale of a moon that could not become the sun. A moon overshadowed by the sun. Webas a human, he was a powerful swordsman and respected member of the demon slayers corps. However, he was never able to step out of the shadow of his twin,. Webhis past also revealed himself to be a distraught and broken man who was sad over his shortened lifespan and with a great fear of death, as well as a grudge born out of. Webkokushibo's jealousy comes from his inability to escape his brother's overwhelming shadow. Yoriichi, the inventor of the sun breathing technique,. Webkokushibo is one of only two known demon slayers who became demons later in life. His past is a dark and rather sad one weighed down by jealousy and an. Webas he was a breathing style user, it took him three days to fully transform into a demon. Eventually, he became upper rank one of the twelve kizuki, remaining at that rank for. As a human, he was born in an age where twins were thought to bring misfortune due to succession struggles. Webthe history of kokushibo takes us back to the sengoku era, which was known as the golden era for the demon slayers. He was the elder brother of yoriichi.
