Mii Popotan is one of the three main sisters in the anime series 'Popotan.' She is the energetic and mischievous youngest sibling, known for her love of costumes and playful pranks. Despite her childish behavior, Mii is caring and deeply attached to her older sisters, Ai and Mai. Throughout the series, Mii provides comic relief and emotional warmth, helping the family cope with their mysterious journey as they travel through time. Her curiosity and innocence are central to her role in the story.