T.M. Opera O is a character from the multimedia franchise and anime series 'Uma Musume: Pretty Derby.' She is inspired by the real-life Japanese racehorse of the same name and is portrayed as a proud, dramatic, and flamboyant horse girl. In the series, T.M. Opera O is known for her competitive spirit, love of the spotlight, and a tendency for theatrical self-expression. She plays a significant role as a rival and motivator to other characters, aiming for the top with her distinctive personality.