Who is Duke from Redeeming Love and what is their importance?

Duke is a pedophile and a pimp, and has a major influence on Angel's personality and psyche. He begins to rape her at the age of eight, and when she is too old for him, he uses her as his highest priced prostitute. Duke is a violent and powerful man, killing those who are a threat to him, or who anger him. Angel has nightmares about him for years after she escapes his clutches. In the end, Angel reveals what he is to the public by carrying his new young child prostitute out of his brothel through the large, shocked crowd, ruining his reputation and stealing his power.