Bart Simpson is an antagonist of The Simpsons. He is the mischievous, rebellious, misunderstood and "potentially dangerous" eldest child of Homer and Marge Simpson, and the older brother of Lisa and Maggie. Even the police of Springfield don't wish to be within 69 miles of this guy (which potentially explains the "Do Not Cross" tape around his house).
Since the age of two, this boy has been constantly plotting plans to annoy the shit out his father. This is also why he gets strangled by said father EVERY. SINGLE. EPISODE!
Bart is mentally unstable as well. He pulls frantic pranks from stealing church money to pranking serial killers. Bart even becomes a douche with his friends and family regardless of the case. He even stole all the spaghetti from the Mushroom Kingdom just to burn it all. This ended up with Mario beating him up. His worst scenario was when he was caught using charcoal in front of Hank Hill, which ended up having Bart hooked up to life support.
After growing up by playing games like Saints Row and Grand Theft Auto, Bart became a pimp and gangster in the streets of Los Angeles. He died in totally unrelated way of falling down the stairs...while robbing a mini mart.