Gumball Tristopher Watterson is the main character and protagonist of The Amazing World of Gumball. He is a twelve-year-old, light blue male cat that goes to Elmore Junior High with his ten-year-old adopted little brother Darwin Watterson and his four-year-old sister Anais Watterson. Gumball is in Miss Simian's class. Gumball also has a crush on [[Penny Fitzgerald, who is also in Miss Simian's class. Penny has a crush on Gumball as well, but they struggle to express their emotions to each other.
Gumball is a light blue cat. On his oversized head, he has six whiskers but most of the time only five are visible because his head is always shown at an angle. He usually wears grey trousers coupled with a tan sweater which with brown cuffs and a brown collar. Like his mother and father, Gumball doesn't wear shoes, and is the only member of the Wattersons without visible eyelashes.
Gumball is portrayed as a fun-loving, imaginative, optimistic, and a very mischievous cat. When his mishaps get himself into a mess, he usually attempts to fix things with somewhat dimwitted ideas, which usually get him into even more trouble than before. No matter how his schemes resolve themselves, Gumball's naivete stops him from learning his lesson. He usually plans his mishaps with Darwin. Like Darwin, Gumball does not appear to notice deception, which may mean that he is too optimistic to notice most negative things around him.