Gyuki

Hibiki is the master of the taiko-based Ongekido Hibiki Style. Because he lost his righteous heart through his desire to become stronger, Hibiki is consumed by his Oni power and starts his metamorphosis into the legendary half-Ox Makamou and half-Oni, Gyuki. As a result, Hibiki adopts a lazy and rude attitude to most people, wears modern clothing, and even attempts to drive Asumu away in an attempt to retire from being an Oni. It is only when Kuuga is about to get killed by a Tengu Makamou that Hibiki decides to assume his Oni form and transforms into Gyuki as a result, wounding Ibuki and Zanki before being driven away by their pupils. Knowing that he will no longer be able to assume his human or Oni form again should he transform into Gyuki, he gives up his Transformation Tuning Fork Onkaku to Daiki Kaito to give to Asumu, who becomes the new Hibiki and must slay his former master as his final request.