Based solely on available sources, Anko is listed as a voice role in the cast section for "Ultra Nyan 2: The Great Happy Operation." These sources provide no specific details regarding Anko's background story, character development, narrative function, species, relationships, motivations, or actions within the story. The documented synopses, character profiles, and production information focus exclusively on the protagonist Nyan and the central conflict involving the crow attacks, with no mention of Anko's participation or significance.