We believe that Ren is tired of being labeled the "bad boy" simply because of where he's from. We believe the PK (preacher's kid) Ariel, played by Lori Singer, is a deeply troubled young woman because of her strict upbringing. And we believe that Reverend Shaw Moore wants to save the rebellious youth in his town. And why? Because his son was killed after a night of drinking and dancing.
Rev. Moore is the major antagonist in this story. The writers didn't do the typical thing and made him strict because of his religious beliefs alone. They upped his conflict in the back story. Rev. Moore lost a child due to the very thing he now opposes. And that gives his character depth.
When we create our villains, it is so important not to make them Disney cartoons. That worked for Walt but it won't work for us. All of our characters need a reason to do the things they do. A good reason. Not just because they're inherently wicked, but because something has happened in their past to make them that way. And even more importantly, they need to think that what they're doing is the right thing. Rev. Moore sincerely thought it was his calling, no, his duty to protect the young people in his town and keep each and every one of them from suffering the same fate as his son. This made his cause noble, if not a little misplaced.
So, to recap, give your antagonists depth by giving them a reason for what they do, and give them a noble cause that is only noble in their own minds. That will make them believable and entertaining enough for the readers to keep turning those pages.