What I look for in any character, good or bad, is whether I can hear him speak. If I can imagine him that clearly, then I can write about him.
Thomas PerryThe characters you refer to as predatory and unsavory are useful. They're the ones who make a novel into a thriller. They're active, and most of the common virtues, the signs of a good person, are not.
Thomas PerryI do want to write about Jane Whitefield again, but only when I have a good enough idea - something I've figured out about her that's news and that's worth a reader's time.
Thomas Perry