Mittens is Stella Starbella's pet.
Mittens is an anthropomorphic alien cat with purple fur who wears a necklace with bell.
Mittens seemed a quiet cat only abble to meow until the end of the episode "The Loose Screw" where is seen singing.
In his youth, his owner, Starbella, was the greatest superheroine in the Yonder Galaxy and fought against Mandrake the Malfeasant, her archenemy and ignored suitor. Eventually she got too old and retired.
Years ago, Mandrake came out of retirement to show all the young punk villains what real villainy was all about. His first easy victory was kidnap the King of Sherblorg 7. However, Starbella, with the company of Wander and Sylvia, soon arrived to stop him, but the trio was quickly trapped by Mandrake. Mandrake then gloated his victory and how he would soon be the greatest in the galaxy, but then quickly made Starbella know how hurt he was that he was never able to conquer her heart, however she quickly corrected him that its his own fault for never trying to just have a good time with her. She then escaped his trap, defeated his robots, and saved the king, Wander and Sylvia singlehandedly, all before Mittens joining in scene and making Mandrake's ship self-destruct. However she did not wish to leave her old foe behind as he fumbled on his computer so she then carried him to safety. The group then had a peaceful tea time on the ship while enjoying cookies, Mandrake included (although while locked in a cage).
Then, Mittens is seen driving Starbella's ship while is singing about her.