A Muse is a character who inspires others. Normally seen as positive, a Muse can easily become negative if twisted in a similar manner to an Evil Genie. Often appearing to an individual or group, a Muse inspires them, often via horrific events of circumstances.

A good example of a villainous Muse is someone who performs grisly misdeeds, which another character take as inspiration for their work, whether they become a "copycat" or something else entirely (such as horror writers gaining inspiration from demons who show them grotesque or frightening imagery which they use in their work).

Often, a villainous Muse will see their misdeeds as a type of art and share their "gifts" with those unfortunate enough to be around them. Usually, a villainous Muse is feared by everyone around them due to them idolizing things traditionally seen as taboo in society, though some exceptionally twisted or desperate individuals may willingly call upon such a Muse when in need of inspiration (as seen above).