The paranormal elements are also rather more pronounced than I recall from the original. Obviously a book in which one can sell one's soul so that his portrait will age instead of him isn't exactly what you'd call realistic fiction, but Creatures of Will and Temper fleshes the concept out with societies of demon-worshipers and, of course, fighting demons.
Really, if this is the book for you, I shouldn't have to say anything else. You're probably already ordering it from your library or your favorite book seller. But I really ought to say a little more than one can get from the blurb, and so I'll say that although the basic concept of this book is a terrific hook, what really makes it is the relationship between young Dorina (beautiful, spoiled, in love with all things aesthetic) and her older sister, Evadne (homely, athletic, and a talented fencer). Ultimately, what matters isn't the search for beauty, or fighting demons, it's sisterly love. And sisterly antagonism, but not so much at the end of the day.
Overall: A