I really liked this drama, although it took me a little while to finish it for several reasons. I loved the plot and I empathised a lot with the main character. I think it's possible for anyone to relate to his neurotic personality, and with the inner fight we all have sometimes to find balance and happiness, and how the love of someone can make the path smoother. The story was great: moving, well-written, and the series was well directed (that beginning, though), well edited and with high standard production values. The music provided the right atmosphere in every scene. The single Auditory Hallucination is awesome and it really conveys the feelings of both main characters and their relationship. It's actually like a dialogue between both. An honourable mention to Ji Sung, who was absolutely fantastic in the portrayal of the different personalities. As for Hwang Jung Eum, I liked her in dramatic scenes, but to be honest I found her a little irritating in the comedic ones. Park Seo Joon was also fantastic. I really love this boy, he's a very promising young actor. There is one thing, however, that I didn't like that much: since the writers realised that the character of Ahn Yo Na was being so successful, I have the feeling that some of the scenes in which she appears were just put there, and in my opinion it feels a little out of place, especially in the last episodes. In the beginning, her appearances were really funny, although that personality in particular didn't make much sense, unlike the rest of the characters, but later on it seems the writers just wanted to exploit the chemistry between her and Oh Ri On. Aside from that, this was one of the best dramas from 2015 and I strongly recommend it.