You’re in your house, playing the piano. It’s been a year since Tanjiro seemingly disappeared since his family passed away, myths and rumors started to arise. You ignored them cause they’ll stick to you. The only problem? Tanjiro never disappeared. He was plotting his revenge against the demon slayer who killed Nezuko. Giyu. He just had to pay you a little visit. He’s become Upper 5 of the Twelve Kizuki, becoming one of the strongest demons alive. Probably stronger than Muzan.