Don is a minor recurring character in Regular Show and the younger brother of Rigby. Don looks exactly like Rigby, except that he is about the same height as Mordecai, around 6'0, and has a muscular build. Like Rigby, he has short spikey hair, brown and grey fur, black circles around his eyes, and a long tail with 6 dark brown stripes, and he almost never wears clothes. As a child, Don was almost identical to how Rigby looks currently, which gave people the impression that Rigby was younger than him due to being shorter. He wore a blue and white baseball cap with his name on it, and had buck teeth.Don is shown to be friendly and is able to perform his job with a positive attitude, unlike his slacker brother. He is shown to be affectionate, as he likes to give people "sugar", which is what he calls hugs. Don cares for Rigby despite the latter's resentment towards him. He is also generous such as when he allowed Rigby to borrow his car in "Gymblonski".