Zang Ye has spent a year waiting at the Bone-Eater's Well for the prophesied girl who will end the war. When Kagome Higurashi suddenly emerges from the well, his wait ends and a sign-in system activates, fusing him with the complete Shikon Jewel. Now armed with foreknowledge of the Feudal Era and powerful new abilities, Zang Ye navigates a world of yokai, sacred trees, and half-demons.

He protects Kagome, confronts the Centipede Demoness, and encounters the sealed Inuyasha, all while hiding the true extent of his power and his memories of a previous life. As events from the familiar story unfold around him, Zang Ye must decide how much to change and how much to let play out, building his strength through daily sign-ins in a dangerous era where humans and yokai constantly clash.