—Ryūkotsusei File:Featured.png File:Padlock-silver.svg.png Ryūkotsusei (竜骨精, "Dragon Bone Spirit") was an extremely powerful dragon daiyōkai who terrorized the Plains of Musashi until he was confronted by the Inu no Taishō and sealed to a cliff face in the Valley of Ryūkotsusei. The wounds that Ryūkotsusei inflicted on the Inu no Taishō ultimately led to the latter's death.