This is one of those Comedy-Romance-Mystery Thrillers with a Supernatural element, and if you are an avid South Korean drama watcher you might liken this to Strong Woman Do Bong Soon. In terms of its writing quality though ... it is just written poorly and acted poorly.

Concept and Execution---
While the concept of the story is very, very interesting the execution was poor. The supernatural element and the thriller element were so gripping that I enjoyed the ride. Unfortunately, the ending had little explanation or intrigue; it was vague and indeterminate as if the writer and director were having a quarrel. There were so many unanswered questions that made me angry. Overall, there was a lot of potential that was wasted in the slow repetitive pacing of the drama.

Pacing---
As a drama watcher, a drama has to keep me hooked and invested for the 16 hours I am investing to watch it. Unfortunately, this drama did not meet that bar. The poor pacing left the story stagnant in the end. There were so many questions that were left unanswered that could have easily been answered with the amount of time wasted

Romance and Comedy---
This was at best average. The romance was a little lacking in my opinion. I could tell that there was shyness in the romance which did not match the characters. But the friendship between the actors was what kept this drama going. The friendship that turned into love was fun to watch as well, but the concept of the show was the most interesting bit. The friendship to romance bit is the only reason I feel inclined to watch this drama again.

Thriller---
Yes! Yes! YES! I loved the thriller in this drama even though it was just a side show.

Acting---
The lack of chemistry between the main leads makes me less inclined to say that this drama had good acting. Their height difference was cute though.

Ending---
I hated the ending (period). This contributed to my lower rating. See Concept and Execution for more info