He is light yellow in color and somewhat human in physical structure in that he has a head, a torso, two arms, two legs, but with a disc-shaped head reminiscent of Pac-Man. His head is very large in proportion to his body, his left foot appears to be backwards when standing still whether he is screaming, moaning or laughing. When not paying attention to anything, his eyes are either crossed or looking in two different directions. His pupils are red in color, and one pupil is slightly larger than the other. When he talks, his mouth opens in two different ways: the way the mouth of everyone else in the show does or like a can lid opening.
He was imagined by Mac's next-door neighbor, Louise, but his debut episode was centered around the inaccurate belief that he had been imagined by Mac. He has an assortment of disorders including gingivitis.
Cheese likes a lot of things, including chocolate milk, potatoes, candies, games, and cereal. He also enjoys repeating the names of these items to everyone he meets. It is debatable that his catchphrase is "I like chocolate milk," as Cheese has uttered this phrase in all of his appearances on the show except for "Cheese A Go-Go" and "Goodbye to Bloo" .
Cheese calls pretty much all liquids chocolate milk, so it can get confusing when he's asking for some drink other than chocolate milk. Another of his catchphrases could be his sucking in of breath followed by a deadpan "Okay." He is also known to sometimes announce "I pooted." Also, he is easily frightened by common objects such as cake, spiders, not having a spoon, and other assorted oddities.
Whenever frustrated or frightened, he screams at ear-piercing tones as in seen "Mac Daddy" when he, Bloo, and Mac went down a giant slope on a go-cart. Despite him loving chocolate milk, he (according to Mac) is lactose intolerant, and is therefore not allowed to have it.
- I like chocolate milk
- I like cereal!
- I like games.
- 'Nother Game!
- Gotta Go! Gotta Go! Gotta Go! Gotta Go! Gotta Go! Gotta Go!
- I'm a cowboy!
- Hi, doggies!
- I pooted!
- I have scurvy!
- I have gingivitis!
- I have athlete's foot!
- I'm a lady!
- NOW WE'RE BROTHER LADIES!
- Weeeeeeeeeeeeeeeeeeeeeeeee (Gasp) Weeeeeeeeeeeeeeeeeeeeeeeee
- Quiet Doggie!
- Beep-bop-boop (he sings these words as lyrics to the tune of the song Mr. Herriman was typing onto the lock)
- Bye lady, lady bye, bye, bye lady!
- Okay, bye Doggies
- I FOUND A CARROT!!!!!
- I like fishy cracklers!
- I like this game!
- Candy candy candy candy candy....candy!
- Candy is broken!
- (inhales) Okay.
- Noooo! *Chocolate* milllllllk!
- HERE'S MY HORSE! *makes noises while he walks the horse on Bloo's head*
Cheese debuted in "Mac Daddy", where Mac believes to have created him. When Mac leaves Cheese with Bloo, Bloo locks him up in the closet, but he somehow escapes. After Bloo looks for him, Mac reveals that Louise was actually the one that created Cheese--Louise explained that Cheese gets out sometimes and that he just made his way into Mac's apartment during the night, to Bloo's relief.
Cheese made a cameo in "The Big Picture" floating down the river of chocolate milk in Goo's imagination.
Cheese next appeared in "Infernal Slumber," visiting a slumber party organized by Bloo at Mac's apartment on a school night, and when Terrence wakes up to tell his and Mac's mother about what is going on, Cheese jumps onto his face and tells him "Quiet, doggy! Shhhhhhhh!"
Cheese's next appearance was in "The Big Cheese", where, after constantly visiting Foster's and annoying the inhabitants while they are preparing for a news story, Mr. Herriman decides to install a security system to keep Cheese out. However, Mr. Herriman inputs the code at random with his back turned, meaning that when he later invites the entire house outside the test the system, they are all locked out, and the only one who knows the code is Cheese, who has memorized the code as a song. Goo eventually manages to coax the code out of Cheese, but in the process of doing so, the entire house is left in ruins, just as the news crew arrive. Frankie manages to turn the broadcast around and uses it to ask for charity. It works, and Foster's gets a new, top-of-the-line security system. Cheese then sets the system to 'unarmed' and enters the house, to Frankie's annoyance.
Cheese also appeared in a re-imagining of "The Big Cheese", known as "The Little Peas". Peas tries to warn Frankie that Cheese is still in the house, when the door is locked, with him being the only imaginary friend still inside. While he fails to open the front doors, when he gets outside, he convinces Frankie to turn the broadcast around and use it to ask for charity.
His next episode was "Cheese A Go-Go," which was part of the Cartoon Network Invaded programming stunt in May 2007. Bloo thinks Cheese, saying "Gotta go..." ad nauseam through the episode, is an alien as seen from a tabloid magazine. In the last few moments of the episode, a voice from what seems to be an alien contacting Earth says 'Cheese' over and over. This leads people to believe that Cheese is possibly an alien. In the following episodes of the micro series, which spread across several Cartoon Network shows, it was shown that the aliens misunderstood Bloo and believed he meant that actual cheese was on Earth.
In the series finale, "Goodbye To Bloo", Cheese moves into Foster's, as Mac moves to Louise's apartment. Because the new residence Louise will live in doesn't allow imaginary friends, Cheese becomes a resident of Foster's, arriving by announcing "Now we're brother roomies!." All the Foster's residents scream in horror. As Wilt screams "I'm sorry, but this is not okay!," the opening animation used through the series is run in reverse, and Cheese gets the last word in by saying to the viewers "Okay, bye doggies!"
- Photographic Memory - Can remember long series of numbers as shown in The Big Cheese.
- Enhanced Flexibility - Can bend and stretch easier than the average person.
- Disease Survival- Can survive the variety of diseases that he has.
- Enhanced Strength - Despite his feeble looking appearance, while it was not shown, Cheese apparently has a great amount of strength as he broke through a door that was locked by Bloo.
- Mac Daddy
- The Big Picture (Cameo)
- Infernal Slumber
- The Big Cheese
- The Little Peas
- Cheese A Go-Go
- Goodbye to Bloo (Cameo)
- Cheese's voice actor is Candi Milo in the series, but in Cartoon Network: Punch Time Explosion and the XL version, it is Tara Strong (who voiced Terrence). He is an assist character in the game who screams loudly to do damage to enemies. In the XL version, he teams up with Billy and Mandy as their synergy partner. When Billy and Mandy perform their synergy attack, Cheese and Billy scream loudly to do damage to any opponents within range (and they can move around when they do it).
- Cheese has a liking for go-karts as seen in "Mac Daddy," and in the video game for Game Boy Advance, a level consists of finding parts for a Cheese go-cart.
- Cheese's head-mesh and smile bears quite a resemblance to that of Otto Osworth's from Time Squad.
- Cheese is featured in three Cartoon Network games, Cheese Quest, Wheeeee, and Utter Nonsense.
- Despite Mac stating that Cheese is lactose intolerant, he never showed symptoms whatsoever upon drinking chocolate milk.
- Cheese briefly lives at Foster's in his first appearance "Mac Daddy", and permanently moves in at the end of "Goodbye to Bloo". But in the video games, he is shown to already live at Foster's.
- Cheese was absent in Season 3.
- His golden trading card statistics in the Foster's Home for Imaginary Friends Leapster game are:
- He is NOT good to have at secret slumber parties.
- He likes tinfoil braces.
- He likes juice
- He was created by Louise.
- "I like chocolate milk!"
- "I pooted."
- "I like cereal!"
- "I'm a lady... Now were brother ladies!"
- "Now were brother roomies!"