Mouse is a field mouse that appears in the episode credits. She is voiced by Vanessa Marshall.
It looks like she is friends with a female snake (who's name could possibly be Gina). She enjoys watching the fish in the tanks, and is a little more short-tempered than the Female Snake. Starting from the first episode, Mouse and Snake always appeared in the end credits, usually talking about what the episode is about such as pets, adulthood, football, humor. She thinks that clowns are funny.