What does Mungo St. John represent in the novel, Men of Men?

Mungo St. John represents the epitome of evil. Called the devil himself by Robyn Codrington, he has a history of doing anything for money regardless of cost to human life or conscience. He is arrested for running slaves - a lucrative prospect at the time - turned in by Robyn when she and her brother Zouga met him, and she realized what he was doing. Louise is Mungo's employee who Mungo rapes, but she grows to love him in some twisted way and allows Mungo to use her as bait to pull scam after scam ever seeking that one big score. He steals from anyone and everyone, loyal to no one.