Itchy is a cartoon mouse from Itchy & Scratchy. His enemy is Scratchy. He usually always wins against Scratchy in their fights and usually ends up killing him. There is only one known episode where Scratchy wins and Itchy is killed.
Itchy first appeared in the old episode "Itchy the Lucky Mouse in Manhattan Madness", in which only Itchy appears, without Scratchy, and Itchy kills an Irish man and Teddy Roosevelt. This was the very first of many episodes where he would appear. His ears resemble Mickey Mouse's, his name is like Oswald the Lucky Rabbit's and he plays the role of Jerry from Tom and Jerry. The Itchy & Scratchy Land is an Itchy and Scratchy theme park. It has parades with robots resembling Itchy and Scratchy which are supposed to be inoffensive and only attack themselves. While on vacation, the Simpsons were attacked by a group of robots, until they used the cameras flashes to short circuit them (the reason flash snaps are not allowed). Itchy and Scratchy also appear in the Simpsons movie, in a short film that the Simpsons are watching in the movie theatre. Itchy (and Scratchy) may be actual residents of Springfield as seen in "Hello Gutter, Hello Fadder".