The story flow is quite perfect. Characters acted well there. I actually liked all the characters there. Their roles are good. I don't see any flaws in the story except for the last few episodes. I just find them weird, I don't really like the ending, felt like incomplete to me as well. If I'm not wrong, this plot is came from a novel (??·????), the ending was exactly like that. There is a continue of the story in the second novel (???????). I hope to see a second season drama for this. I just don't feel so good for that ending... However, overall, everything is good, the story is quite well connected and understandable. If there is really a second season of this drama, I would recommend you guys to wait for the second season to complete before you start this drama. The first season ending was really weird like what everyone is talking about... I would really change the ratings if there's really second season of this drama :). I'd really enjoyed it.