Cosmo (コスモ, Kosumo?) is a main character from the anime series Sonic X. She was a female child of a plant-like alien species whose homeworld was destroyed by the villainous Metarex, who, in the years that followed, left Cosmo as the sole survivor of her kind. To thwart the Metarex's ambitions for universal dominance, Cosmo joined Sonic the Hedgehog and his allies in their war against the Metarex, eventually becoming a love interest for Miles "Tails" Prower. In the end however, she sacrificed herself to defeat the Metarex for good.