If you're after a fast paced drama full of action and plot twists, this isn't it.
However, I cannot emphasise how much this drama means to me; it is absolutely beautiful and a bit haunting too. Just like the music, actually. The cinematography is also really good.
But I feel like I should warn others before watching it: If you have depression, please be careful. This drama will affect you emotionally and it is the only drama where I have cried for the majority of episodes.
In saying that, though, there are happy, cute, heartwarming and funny moments in this too. It is a slow paced drama, something I usually avoid, but there's something about it that just keeps drawing me back to it. I have watched it multiple times since it came out. I have the soundtrack. I often rewatch scenes just for the cute or funny moments.

I highly, highly recommend this drama.