"I will never forgive him. I will never show him mercy. I'll kill you, Kibutsuji Muzan!!!!" A boy as normal as you and I. All he had was his sister, his home, and a dream. But after everything was taken from him, he realized something. "Not everyone can be saved". Despite this he picks up a blade. He's not a hero nor a saint. He's a nameless swordsman born under the night sky. After being taught a Breath Style, what will he do when the person who taught him is working for the same man he pledged to kill.