Mephistopheles (also Mephistophilus, Mephistophilis, Mephostopheles, Mephisto, Mephastophilis and variants) 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 version of the Devil.
Read more about Mephistopheles: In The Faust Legend, Outside The Faust Legend, Interpretations of Mephistopheles