Nichirin Sword? What Does Zhanyue Have to Do with Me?

After being defeated by Ulquiorra in the Hollow Palace, Kurosaki Ichigo traveled to the world of Demon Slayer: Kimetsu no Yaiba. There are no Hollows here that covet human souls, instead there are evil spirits that eat human flesh and blood. And when his spiritual pressure was at the bottom, his abilities were limited, and Zangetsu couldn't kill ghosts, he actually encountered the ghost king Muzan and was named and praised! Even if it's a headwind start, the Demon Slayer's Nichirin Sword will not be as good as Zangetsuka in his hand...