I loved this drama so much. I don't know even why. Maybe because of it's amazing plot. The story is the best thing about this drama. It keeps you hooked to this drama since episode 1. All the scenes in the drama is simple and makes sense. Nothing is too unrealistic. That's the best thing about it's story. There is also some good plot twists.
I finished the whole drama in just 4 days. Keep in mind that this drama has 21 episodes. I can't believe I finished the whole drama in just 4 days. The story is so addicting. All the actors did an wonderful job. This drama has season 3 ongoing. I haven't started watching season 2 yet. I feel like season 2 also will be as good as season 1.
If you are thinking about watching it then please do so. I am telling you will not regret it.
And about the anger thing. You will feel so much anger while watching it. You will want to break things. I got so angry that I wanted to slap some of the characters in the drama so much. It's very frustrating. Which is a good thing if you think about it.