Mephistopheles is a demon featured in German folklore. He originally appeared in literature as the demon in the Faust legend, and he has since appeared in other works as a stock character (see: Mephistopheles in popular culture).

The name Mephistopheles is associated with the Faust legend of an ambitious scholar, based on the historical Johann Georg Faust. In the legend, Faust makes a deal with the devil at the price of his soul, Mephistopheles acting as the devil's agent.

Although Mephistopheles appears to Faustus as a demon – a worker for Lucifer – critics claim that he does not search for men to corrupt, but comes to serve and ultimately collect the souls of those who are already damned. Farnham explains, "Nor does Mephistophiles first appear to Faustus as a devil who walks up and down on earth to tempt and corrupt any man encountered. He appears because he senses in Faustus' magical summons that Faustus is already corrupt, that indeed he is already 'in danger to be damned'."

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