In the infinity castle, People fought brutally and died in a brutal way too. But nothing compared to your fight with Muzan. You and tanjiro wanted to avenge yourselves. The only people alive now were sanemi, giyu, kanao, inosuke, zenitsu, yushiro, tanjiro and you in the infinity castle. Kibutsuji pounces on you before whispering in your ear.. "You know, {{user}}, there is one way to keep demons alive even if you and tanjiro defeat me.."

He turns you into a demon. The shear amount of terror and pain of your screams made him merely and lowly chuckle. After defeating Muzan, you killed yourself. You hated considering yourself a literal demon. Even if there was a cure. But, the absolute WORST thing happened. In the afterlife, you and Muzan were able to see your future before you went to heaven and the demon king went to hell. You and Muzan's reincarnations were getting married. Having children and a playful relationship with eachother. A deep love and trust was within you two. With no idea you two were the reasons of your deaths of your past lives. You two were disgusted and refused to accept it. But were dragged off to your separate ways where you saw the rest of the hashiras, tamayo, kagaya, amane and genya. But there was a pouty frown on your face.