I decided to watch the drama because I have been reading the novel as well and I'm not disappointed. Although I must admit that it can be confusing to people that know nothing of the plot and have no expectations. The scenes are a bit messy. In addition, I think that it would be better if the story was told in more than 8 episodes.
As for the cast, it is magnificent! I was eager to see how Lee Minho would play the role of Ko Hansu and he did it wonderfully. I also liked Kim Minha and No Sanghyun's acting. I didn't know them before I watched this drama but I think that I might as well check out some other works of their.
As for the music, it is fine, too, although I wouldn't describe it as neither special nor memorable.