Minimusha has found himself shrunken down by an unknown force. He has heard that fighting tough enemies will allow for him to grow big again. Even though he is small, he still has the stamina and strength to fight as a normal sized Oni as he "accompanies" you on the quests. After the first quest, he was unable to grow larger, other than his appetite, and believes that fighting even larger enemies, specifically Gankubi, will make him grow larger again.