NEMO!
Allen from Allen GregoryLil' Abner
Jade or Jackie Chan from Jackie Chan Adventures.
A Chartoon Character that starts with the letter D is Donald Duck and Daisy Duck from Disney Daffy from Looney Tunes Warner Bros and this might count The cartoon Movie Ice Age Diego
Easy, Nelson, the bully
Nemo
InuyashaIno(Naruto)
Luigi
NEMO!
you mean the letter U? UnderDog
Mickey Mouse
Huckleberry Hound
Elmer Fudd
MICKEY MOUSE
Scooby Doo
Krazy Kat .
Voltron "Autobots"