Chum Chum is the show's deuteragonist as Fanboy's best friend and sidekick. Although he is younger than the other main characters, he is still in the same class as them. Show creator Eric Robles explained on the Nickelodeon message board that this is because Fanboy snuck him into his class and the teacher never noticed the age difference. Chum Chum is extremely energetic and high-spirited, and possesses an indomitable enthusiasm and childlike jocularity. Chum Chum has brown hair, wears a black eye mask and gloves, an orange and yellow uniform with his logo on the chest, a yellow cape, black high-top sneakers, and his underwear on the outside of his costume. In the pilot from Random! Cartoons, Chum Chum wears an orange collared shirt with yellow buttons on the chest instead of his logo. Chum Chum seems to be incapable of achieving more than 3 points on Boog's "Chimp Chomp" video game, although Chum Chum is ecstatic even when he loses.
Chum Chum appears as a playable character in Nicktoons MLB. He throws left-handed.
- Screw: ****
- Slider: ***
- Curveball: ****
- Changeup: *****
Nicktoons: Toons WarsEditFanboy appears as a playable duo character along with Chum Chum in Nicktoons: Toons Wars.
Brain Swing is Fanboy and Chum Chum's neutral special. This move is preformed by Fanboy, he slams his head down and the top of his head goes open and his brain swings out and goes forwards.
Frosty Freezy FreezeEdit
Frosty Freezy Freeze is Fanboy and Chum Chum's side special. Fanboy will grab a milkshake with Frosty freezy Freeze and will shake it give it to Chum Chum who then opens the top and fires the inside of the shake forwards.
Chum Throw is Fanboy and Chum Chum's down special. Fanboy lifts Chum Chum up and throws him upwards. While Chum Chum is in air he will spin in the air. When preformed this in air Fanboy does the same only falls into a helpless state. This move can be used as recovery for Chum Chum.
SlingFan is Fanboy and Chum Chum's down special. Chum Chum grabs Fanboy and then puts him into a giant slingshot and then holds it back and fires Fanboy forwards. Fanboy holds his fists forwards so he can damage the opponent.
Ice Tornado is Fanboy and Chum Chum's War Strike. Fanboy and Chum Chum both drink a XXL Frosty Freezy Freeze and then burped very hard while they had an ice breath, They keep burping for a few seconds. Everyone who gets hit by the ice "tornado" receives massive damage and get frozen mostly one attack after that will KO them.