Recently I finished watching season one of the FX series Legion, and while there are a few weak points, overall I thought it was pretty good. I was particularly struck by how they handled what I’m going to call the demon. They do eventually reveal the origins and nature of this demon, but I’d rather not spoil that for those who have not yet seen it.
A good story has a protagonist, goals, and opposition. Opposition includes obstacles and forces of nature, but typically opposition also takes the form of a character. Sometimes the opposition is another protagonist, leaving the audience to choose who they want to root for, but many stories include at least one villain, a character that is definitively “wrong”. Villains can be narrative or mechanical.