Fujiko Fujio A's Mumako is a TV Special that comprises three short stories. Each story features its own protagonist, who suffers from some kind of stress caused by societal pressure, and a corresponding antagonist who is the primary source of the aforementioned pressure. The only shared character across the stories is the titular side character Mumako, who by the end of each story grants a twisted interpretation of a wish which physically transmogrifies the main character. At the end of each story, the protagonist's new ghastly form is discovered by the corresponding antagonist. The titles of each story are an allusion to the nature of the transmogrification. In order of appearance, the stories are titled Castle, Transformation, and Slough.