It's odd that reviews nor the description don't explicitly call out what the main premise of this show is, which is under age prostitution and human trafficking in S. Korea.
At first, I hoped the main character was some sort of hero trying help trap and catch clients seeking under age prostitution. But the plot just gets twisted around the same business of under aged girls selling their bodies.
What a dark and disappointing show. I stopped watching after 5 episodes once it was apparent that it's not some rescue story.
Yes, the plot is twisted and pulls you in. I'm sure once you get past the under age prostitution bit, it's a fun show. But I hope you don't get past that. Forced or voluntary, under aged prostitution is not a subject we should take lightly.