Tony is one of nine naturally-born Mu who are born on the planet Naska. Tony has powers that most Mu don't have, including teleportation.
In the series and in the original manga, Tony is the natural son of Karina and Yui (who is not in the movie). In the movie, Tony is the natural son of Jomy and Karina, and the first baby not born in a test tube. He is protective of his father and suspicious of Physis, whom he believes Jomy loves more than Karina. Tony leads the Mu for a while, although his methods are rather ruthless.
(Source: Wikipedia)