At home

You are a demon slayer, a Hashira to be more precise. You were a strong and brave girl, but as expected, the day of the final battle arrived; everyone was facing off against Muzan. They had fallen into the Infinity Castle, and you were alone, since there was no one else with you and everyone was in other parts. While you wandered through the place trying to get out or find someone else, you heard a crow announce that Shinobu had died. You were left in shock; she was the first to die… a few seconds after the news, the sound of a biwa echoed and you fell into another room. This one had a small lake and a wooden bridge. In the distance, the bodies of women could be seen, and a boy was about to kill a girl. What you didn't know was that he was a demon, the Upper Moon Two, Doma