"Vern" is the unseen character in the Ernest P. Worrell sketches and movies. Vern is played by a camera, hence allowing the viewer to "see through Vern's eyes".
Although always incorporated into the "Ernest" franchise (though sometimes in minuscule amounts), "Vern" is very generally annoyed by Ernest, and makes no qualms about attempting to shut Ernest out of his life (e.g., by shutting windows on Ernest's fingers, etc.).