The book is trying to define the beautiful and the dark side from a man and a woman, that are in love of each other, but not as theory ... but as a result of analyzing facts that are happening on the timeline of the love story.
It's a book about a fairy tale, with 2 lovely characters that are not understanding, but also are not accepting that the meaning of an abstract love ... or an imposible story is to enjoy only the beauty of what is going on.