Hanyū, a figure of intricate heritage and supernatural essence, emerges as both the ancestral forebear of Rika Furude and the true incarnation of the village deity Oyashiro-sama. Her striking features—light purple hair, vivid purple eyes, and dark horns marred by a sacrificial crack—reflect her dual existence as mortal descendant and divine entity. She alternates between traditional shrine garments, modern school attire, and a transcendent form marked by crimson pupils when invoking her powers. Centuries ago, her clan, Hai-Ryūn Ieasomūru Jeda, sought harmony with humans in what would become Hinamizawa. Mistrust of her demonic lineage ignited conflict, culminating in her ritual execution by daughter Furude Ōka via the sacred blade Onigari-no-ryuuou. This sacrifice birthed the Watanagashi Festival and enshrined her worship as Oyashiro-sama. Lingering as a spectral presence, she remained isolated until Rika’s birth granted her first tangible connection to the living. Hanyū’s powers span traversing the Sea of Fragments, orchestrating time loops reset by Rika’s repeated deaths to alter fate. Yet her waning strength erodes memories between cycles, with her fractured horn mirroring Rika’s fragmented awareness. She manipulates time, teleports, and subtly influences those afflicted by advanced Hinamizawa Syndrome, trailing them in remorseful penance—a presence that unwittingly deepens their descent into madness. Initially a maternal guide teaching Rika survival, Hanyū evolves into a weary companion through endless cycles of tragedy. Tensions arise, yet her loyalty persists, clinging to hope even as despair looms. Later, she assumes a human disguise as a transfer student, embedding herself within Rika’s circle to covertly oppose threats like Miyo Takano, leveraging divine insight and strategic cunning. Expanded lore unveils ties to Eua, a higher-dimensional being who dismisses Hanyū as a flawed fragment born from her own shattered horn. Console-exclusive narratives delve into her past as a demon goddess—her union with Furude Riku, Ōka’s birth, subsequent corruption, and redemptive sacrifice. Driven by guilt over cyclical horrors, Hanyū vacillates between despondency and resolve, adopting an imperious divine mantle to confront foes like the Mountain Dogs or Takano. Her journey converges in Matsuribayashi-hen, where collective defiance shatters the time loop, securing a fragile peace forged through centuries of perseverance.