Nelson Muntz is the one of the bullies of Springfield Elementary. He is often seen with Jimbo Jones, Dolph Starbeam, and Kearny Zzyzwicz, sometimes as friends, sometimes getting beaten up. His father left him to go out to by cigarettes, and never returned. His mom has had several acting jobs. He has had friend relations with Bart Simpson in some episodes, while he beats him up in others.
When it comes to his parents, Nelson shows a bit of a soft side as his lifestyle with his folks is far from pleasurable. His dad left him and his mom, and often he wonders when he'll come back. He lives in a shack house with his mother, a very gritty spot.
His catchphrase consists of the famous "Ha Ha!" trademark laugh.
[Looking at his own reflection]
Nelson: Haha! Hey... That hurt... No wonder no one came to my birthday party...