Nicole is a light blue cat. She has six whiskers, just like her son, but all of her whishers are always visible, unlike Gumball. She wears a white work shirt with a grayish-purple skirt. She also wears a rainbow pin, which may simbolize her workplace, the Rainbow Factory. She looks similar to her son.
Despite caring her family and able to work long hours without stress, Nicole has a short, fiery temper. It is this temper, that is shown in The Responsible, that makes Gumball afraid of her more than anything else. She hates being talked-back to, as shown in The DVD when she punched a hole in the door in response to Gumball's talk-back. Nicole can have a difficult time relaxing, as shown in The Painting, and usually breaks everything in the house just for being able to clean it all up.
- Nicole is great at improvising, as shown in The Spoon when she used the frosting on her rope to get Richard to bite off the rope that was holding her.
- Nicole is very athletic, as she can knock people out with a sausage and has done many stunts in the chase in The DVD.
Mom is the only truly responsble person in the family. She works long hours at the Rainbow Factory to put food on the table.