Koko Ninna-Nanna is a Melos Warrior from the anime The Melody of Oblivion. She is very young and leads a group of insurgents that she calls an armed theatrical group, fighting against a society controlled by monsters. Despite her youth, she is smarter and more mature as a warrior compared to her fellow warrior Bocca, and she possesses an adult-like sense of humor that she uses to cope with her tragic past. Her primary motivation is to resist the monster-dominated world and protect humanity. In the story, she acts as a leader of a resistance faction and takes part in battles against monster forces. Her key relationships include working alongside Bocca and other Melos Warriors, though her dynamic with Bocca is marked by her greater tactical insight and experience. Throughout the series, her playful demeanor contrasts with the weight of her background, and her development involves confronting her past while continuing her fight. As a Melos Warrior, she has enhanced combat abilities, and her signature attack is called Four Card, a reference to the poker term for a very strong hand. Her surname, Ninna-Nanna, is the Italian word for lullaby, which reflects the thematic resonance of her name.