The Three Realms as the Main Stage, the Nine Domains as a Supporting Cast

From a bullied boy to a guardian of the Three Realms: after accidentally obtaining a damaged fragment of a Boundary Stele, he awakens some of a guardian's powers and sets out to find the scattered stele fragments, repair the barrier between worlds, and fight the Void Ash and world-destroying beings. In the end, he transforms from a "good-for-nothing" into the protector of the Three Realms.