Sonic the Hedgehog (character)
Cosmo: Cosmo is a female child of a plant-like alien species whose homeworld was destroyed by the villainous Metarex. She is an friend of Sonic the Hedgehog and his friends, and many see that her primary purpose in the series is that of a love interest for Tails. This is because the two characters are of the same age for one another. She is only in Sonic X.