This is hands down the best k-drama I have seen till date.
Everything from storyline, acting and OSTs are splendid. Although it has a sad ending but the actions of each character seems justified & leaves an impact in the final outcome.

Cast:
Every character has aced their role to near perfection. Conversation between all the main characters, their respective actions and following repurcussions pace the show in a very balanced way.
Eugene Choi and Go ae shin's relationship and the way of embracing each other is represented in a very beautiful manner.

OSTs:
Each of the songs hits very deep. All the songs are so beautifully composed.

Glad that I watched this masterpiece and it will have a lasting presence in my memory.
Hope to watch it again sometime...