In the end, the hero and heroine end up married with 2 children, living in a mansion overlooking the sea with a love life that involves some bondage and discipline, a little "kinky" perhaps but a long way from the depravity in which the hero is immersed at the beginning of the book.
I found it worth reading for the psychological insight into the characters, seeing how depraved behavior can be traced to childhood experiences and how, with love, understanding and compassion, it is possible for a person to reform themselves into a reasonable human being.
Woe to the person that marries a person with such issues. The love story does sound interesting but isn’t that a dangerous message. Most of the time it doesn’t seem to work and messes us the “reformer”. That is how I advise my daughters anyway.