Jinx the Cat
Jinx the Cat. His co-stars were Pixie and Dixie (mice)
You might be able to count the Jailbird (early name of Snake) on The Simpsons. Also, the old guy Jasper.
Johnny Bravo
Jonny Quest
Johnny Test
Jerry (Tom and Jerry)
Josie (Josie and the Pussycats)
Joey Wheeler (Yu-Gi-Oh)
Jimmy Neutron
Jake Long (American Dragon)
NEMO!
Allen from Allen GregoryLil' Abner
If you are referring to the cartoon characters from the Simpsons, the answer is Itchy, the cartoon mouse.
Ant and Aardvark .
Gh? charecters? no no no.
ichigo kurosaki
Fred Flintstone, Fat Albert and Felix the Cat are cartoon characters. They begin with the letter f.
Underdog
Alvin and the Chipmunks are cartoon characters. They begin with the letter A.
Nemo
Luigi
NEMO!
InuyashaIno(Naruto)
you mean the letter U? UnderDog
Elmer Fudd
MICKEY MOUSE
Mickey Mouse