In his former life, he is Arima Kihei (有馬喜兵衛, ?) and he was originally a swordsman in Musashi's original world. After killing a young child in the Miyamoto village, he encountered Miyamoto Musashi when he was just passing by on that mountain road, he challenged Musashi and was killed.
As he died, and his grudges turned him into an oni known as Sukeroku in Onigashima Island.
Musashi Trial QuestEdit
Sukeroku appears as a cowardly oni in Musashi's trial quest, eventually regaining his memories. He attempts to kill her again, but is defeated.