T.M. Opera O is a charismatic and highly dramatic horse girl from Uma Musume: Pretty Derby, known for her theatrical flair, confidence, and self-proclaimed royal presence. She is one of the standout competitors in the series, often portraying herself as the "Emperor" and striving to dominate the racing world with elegance and authority. Her character adds humor, intensity, and strong ambition to the story, while also serving as a major rival and memorable personality among the cast.