I was absolutely whipped for this drama when it first started. The chemistry between the FL and ML was terrific. I used to look forward to new episodes. However, I wasn't a fan when the ML and FL started dating and their personalities changed a lot. ML, who was known for his cold gaze and strict behavior suddenly acted like a school boy. I would've been happier if their dating was written differently...more subtle changes rather than throwing it all the at viewer's face.
Another thing I don't understand is the recent trend of inserting murder mystery and/or crime into a storyline. It felt out of place and absolutely unnecessary, especially for episodes 11 and 12. The story wouldn't be so good if it was 'just' an office romance with a sparkle of supernatural. The last two episodes made me feel like I was watching a completely different drama.
I still liked the drama as a whole but the more episodes I watched, the more my interest decreased. The writing had a lot of potential in the early stages but somewhere around episode 7, it started to go downhill. Overall, I hate to say it's an okay drama. The ending felt rushed and could've been executed better.