Butterflies for Yureihana (Demon Slayer X Male Reader)

Young (Y/N) was a young boy who's who's family was murdered by demons. On the run with his elder sister, they come across a mysterious man who takes them in, but happiness isn't guaranteed. After the death of his last family member and escaping near death, he would later be saved by the Flower Hashira who takes him in and helps train him in the buttefly mansion.
His adventures lead him to Tanjiro Kamado, and with that he later joins Tanjiro on his adventures to save his younger sister from Muzan's curse. While going on his own journey to satisfy his own selfish desire for vengance, and honing his own breathing technique that he designs to suit him.