Extremely intelligent, but unable to really talk. Sometime he figures out things before Kim and Ron, but is unable to warn them. He is also stronger than a normal mole-rat. Rufus is sometimes mocked because of his apperance, but is always defended by Ron or Kim.
He shares Ron's love for Nachos.
In Kim Possible: The Movie, in a alternative future he is a resistence fighter. There he is really muscular and able to talk. His catchphrase is to always offeri Kim and the others a cookie everytime they do something good.