Kyubei was the proprietor of the House of Black Leaves sake house. He had a daughter. The sake house burned down in 1149 following the deaths of four soldiers sent by the Steel Chrysanthemum at the hands of Kaneka and Masakazu. Masakazu told Kyubei to burn down his house, take his family and flee or else the Steel Chrysanthemum would suspect he had something to do with the killings.