Cheekums appears when Li'l Gideon releases Mabel and Dipper Pines out of a jar and puts them in his bedroom, Li'l Gideon tells Cheekums to guard him, however, he does not. Mabel tries to ride him, but doesn't, and Mabel calls him a Big Ol' Dummy. Dipper then pokes him with an ear waxer.
Cheekums is a light brown hamster with a pink nose and brown freckles, he also has brown inside of his ears, whiskers, and he has two front teeth (buck teeth) and has gray claws.
Cheekums is described as a "Big Ol' Dummy" and is very unresponsive and doesn't react to any commands.