When Sticks' friends tell her to be nicer to (non-anthropomorphic) animals, she becomes attached to a slime-belching robot dog named Buster.

When Amy realizes that Sticks is a pack rat, she forces her friend to have a garage sale to get rid of all the junk that's accumulated in her burrow. During the sale, a secret locked door to an underground world is removed and an invading horde is set free.