In this song, Eminem trolls his fans. He talks about having a crowd, as he calls them, of DEVOTEES, who try to imitate him in everything, although in reality, they are just dumb kids who don't even understand his lyrics and simply think he's cool.
It's funny that the chorus of the song is very familiar to me: every other classmate of mine sang it five years ago. They didn't even realize that they themselves were the characters in this song and were being thoroughly ridiculed in it.