Wesley Lawrence Willis was an American musician and visual artist. Diagnosed with schizophrenia in 1989, Willis began a career as an underground singer-songwriter in the outsider music tradition. Willis' songs are typically partially spoken in an MC style, and partially sung in a nasal and out-of-tune manner reminiscent of punk rock vocals. They feature bizarre, humorous and sometimes obscene or absurd lyrics sung over backing created by using the auto accompaniment feature on his Technics KN keyboard. His songs cover a wide variety of topics, with mental illness and consumerism being the most prominent themes. He is best known for songs such as "Rock N Roll McDonald's" as well as a series of songs where he would directly insult his demons.

Outsider music is music created by self-taught or naïve musicians. The term is usually applied to musicians who have little or no traditional musical experience, who exhibit childlike qualities in their music, or who have intellectual disabilities or mental illnesses. The term was popularized in the 1990s by journalist and WFMU DJ Irwin Chusid.