Joe was Willie's pet fox. He had been domesticated via Dmitry Belyaev's breeding program and was docile and liked people. He also was plump with longer, thicker and fluffier fur and his muzzle was half the length of his wild ancestors. All this was intended, making him cute and attractive to humans.
One day Willie took Joe for a walk and came across a neighbour named Fritz out walking his two dogs. Joe was scared of the two and with good reason since they once chased him home and would have had him for a snack if they caught him. Fortunately, the dogs were leashed but Joe sat behind Willie's heel while the two talked. He was relieved when Voice ordered Fritz to go home and he took his dogs with him.