My review comes three years late after finally getting a chance to rewatch it.
I had followed the drama while it was airing and remember losing interest half way, watching the final episode and skipping through the scenes around Episode 11 - 14. It was this rewatch that finally made me understand why I found certain parts less than interesting.

A young prodigious man is tricked into the service of a supernatural being, Jang Man Weol, after his father was conned into making a deal with her 20 years ago.

Then, we get to see an exclusively detailed view of how Gu Chang Sung's entire life gets turned upside down as a result. I admit, he was an unsuspecting and unconventional male lead --- half of the drama, he is stuck in a state of constant dilemma, attempting to make decisions and also learn about his mysterious master, Jang Man Weol, the owner of Hotel del Luna where he is forced to work.
Jang Man Weol had a lot of "pecadillos" rather than being a genuinely evil being. But, I consider her very first decision of tricking Chang Sung's dad into selling his son to her the most cruel one. Burdened with the punishment of running the Hotel for 1300 years, she awaits to serve vengeance to the ones who had forced her through this dark path. It is now upto Chang Sung to see that she crosses the afterlife safely and remove her resentment.

I loved the three ghosts who served the hotel -- Miss Choi, Mr. Kim and Hong Joon. They were humourous. I also adored the rapport between Chang Sung, Sanchez and Mi Ra. I sometimes wished that the story focussed more on the humans than the ghosts. The ghosts whose tales were prominently followed were all emotionally depressing. I did not find them boring, as each one had a pivotal role in changing Man Weol's view on life.

The major events in the story are pre-planned by the 'deities'. And everyone of them managed to get on my nerves except for Police woman Ma Go and Medicine Ma Go. The way they dealt with the lives of living beings like cards was difficult to watch.

Last, but not the least... I could feel why Jang Man Weol sought revenge for centuries. This was also the weakest point in the drama for me. The backstory of a very important character was almost laughable. It was a moment that I waited for as I wished that it would make me find him redeemable, but in the end, he sounded like a coward.
I suddenly understand why Chang Sung was the male lead instead of him. He might not have anything heroic happening around him, but he definitely had enough intellect and loyalty in him.

I wonder how hard it was for IU to act as Jang Man Weol. She had around more than three outfits per episode and I can't imagine how exhausting it was for her and the stylists of this show. (I loved JMW's style though!)

The soundtrack of this drama is absolutely unforgettable. I can remember almost all the songs even after three years.

I do find the drama absolutely delightful and enjoyable. It's not a masterpiece, but the brilliant performances by the cast, beautifully shot scenes and a story that completes a satisfying circle is definitely worth giving a try.