Two things in this movie that really caught my attention was the cinematography and the acting.

The Cinematography was great. If I could, I would had given a 10 just for that. And the makeup, that was also really good. It was realistic and really detailed.

Second is the acting. Shin Rin Ah, she was absolutely amazing. I really liked how she performed. From the beginning of the movie you get drawn into her character, because of the way she portrayed it. She is going to be an amazing actor in the future.
And Lee Joon Hyuk. Even though he had a short screen time, I loved his part. Actually got me scared a little, at first.

If we talk about the story, then I would say that it is lacking in places. There are parts in the movie that has nothing to do with the story. And a lot information wasn't given. You kind of have to guess your way around it. Also ending wasn't really satisfying for me, cause it still leaves me with questions.
Nothing major.

Its a good movie for a one time watch, if your looking for something new to try out.