Toa

Toa is a mysterious girl who saves Jin from a dragon in the first episode. She is shown to have remarkable athletic abilities, extraordinary strength, and accelerated healing capabilities, possibly due in part to the fact that she is a dragon. In her dragon form, she is immensely powerful; she is able to take on more than two other dragons at a time. She is referred to as the "Album" by the ISDA, who wishes to capture her in order to retrieve information on the original dragons from Thanatos. She calls Thanatos 'mother', and her mission on Earth is revealed to be the retrieval of the dragon eggs possessed by the ISDA.

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She later admits to being the one that collided with the shuttle that killed Jin's family. She got the name "Toa" after retrieving half of a bracelet that belonged to Jin's sister, Ai. Before the accident, the bracelet had "To Ai" engraved on it, but now it only reads "To A".

In the manga, she is part of the Dragonauts and is partnered with Jin. Though she possesses all the abilities as her anime counterpart, she is shown to be very klutzy, which often infuriates Jin. Despite Jin's seemingly cold attitude towards her, she remains very loyal to him. (Source: Wikipedia)