An adventure story needs a few motivated villains.
But what constitutes villainy?
Whether through misfortune, cravings for power and wealth, or fanatical political ideals, each villain has a particular reason for their mindset and actions. Some start out as perfectly legitimate positions.
However, being dedicated to a Cause often means being blind to any other point of view. Thus the angry, stubborn fanatic behaves in a way that defines him or her as a villain. Torture, mutilation and murder are sometimes part of the job.
And of course in a Regency tale worth its salt there have to be Rakes.
So in The Rake's Challenge, among other villains there are four Rakes on the prowl. Two are brothers, young and enjoying life. One is [ahem] the Prince Regent and then there is Sir Bilton Kelly, whose job is to find pretty young ladies to entertain the Prince.