What I liked:

The premise: Middle-aged man with relatively affluent lifestyle and well-established career encounters poor, miserable young girl and the two form an "unlikely" bond because they relate to each other's suffering. Also, a meditation on all the different types of suffering -- of a man being cheated on by his wife, of a girl victimized by society and circumstances, of a lonely aging woman deserted by her lover, etc. Suffering is something we all share, in one form or another, so it is a universal theme.

The slice-of-life scenes: Really adds warmth and light to the dark world of this drama. I loved the relationship between the brothers, and the late-night walks around the neighborhood, the happiness tinged with sadness. Sometimes a bit overdone, but generally well-made.

The mood: Not everyone gravitates towards darkness, but if you are in a particular mood, this drama hits the spot. The heaviness and sadness interspersed with lightness and warmth, that play of chiaroscuro, make for a really satisfying tone.

Some of the dialogue: I really, really loved the little nuggets of wisdom dropped here and there, about people struggling all their lives to chase after a goal that in the end does not bring real happiness, about the futility of proving yourself to other people, etc. I also liked the addition of the Buddhist monk. These almost saved the whole drama for me, but not quite.

What I didn't like:

First and foremost, the fact that Ji An is never really made accountable for the things that she does. The viewer is set up from the very start to empathize with Ji An, to feel her suffering, to view her as a victim, and to understand why she does the things she ends up doing. Set up is the right term to use though because the pathos is laid on thick from the very start -- sick grandmother, having to eat other people's leftovers, being hounded and beaten repeatedly by a loan shark with a grudge, having only stolen instant coffee as a small comfort and pleasure against all the darkness of the world. Yes, yes, and yes. HOWEVER, as the drama progresses, we see Ji An committing dastardly deeds -- stealing money (bribe money, yes, but still stealing), offering to ruin people's lives and reputations in exchange for more money, blackmail, wiretapping, stalking, and generally just a total disregard and disrespect for other people's privacy. Yes. She needs money. Yes. She is taking care of her sick grandmother and she is desperate. Yes. She was and still is being victimized by a loan shark. Yes. She indeed has a very unfortunate life. BUT THAT IS NO EXCUSE TO HARM, DISRESPECT, OR VICTIMIZE OTHERS. Everyone has a story. Everyone has some aspect of their lives that is relatable and pitiful. Even serial killers. Even mass murderers. That doesn't mean they should not be held accountable for the things they do. It is one thing for Dong Hoon and his guilty wife to understand Ji An and even to instantly forgive her for listening to their private conversations whenever she wanted to (heck, she could even have eavesdropped on their lovemaking. "Luckily," they were having marital issues). It is a totally different thing for them to act very irresponsibly and to even help her get away scot-free without being held accountable for everything that she did. Stalking and wiretapping someone ARE SERIOUS INVASIONS OF PRIVACY. In the drama, the wiretapping is used as a tool to get Ji An to fall in love with Dong Hoon, and so the scenes of her listening in on him are portrayed in a tender, loving light. But in actuality, she is committing a grave crime against his person, and it is all very creepy and disrespectful. The writer could have had her do some time in jail, or do community service at the very least, but having Dong Hoon instantly forgive her (seemingly because he just was desperate to see her) and even help her after he finds out is, I think, poor writing and horrible decision-making. Whatever kind of bond they formed, a wrongdoing is a wrongdoing and should be treated as such. Even parents reprimand their children when they mess up.

The nature of the bond between Ji An and "her Ahjussi." I understand the writer wanted to establish a deep, undefinable bond between Ji An and Dong Hoon, but in the end it became very obvious that Dong Hoon was feeling more than just fatherly or brotherly love, friendship, or affection towards her. There were too many scenes of him scanning the streets for her, missing her, almost being obsessed with her. This could have been done very well and much more subtly. The bond need not have been romantic of all, on either side. It could just have been that -- a deep bond -- and need not have crossed any lines. One good example of this, done right, is in Leon: The Professional. Or they could have opted to add subtle, ambiguous hints. It is not necessarily just the age gap nor the fact that Dong Hoon is married that made these scenes cringey for me, but definitely those did play a part. Personally, I thought it was unnecessary to add romance and desire to the mix. There could have been, maybe in their last scene together, something, a "maybe," in the way he looks at her or holds her hand, but even that may be too much. It just was...cringey and inappropriate somehow, and, as I said, totally unnecessary.

Overall:

The drama definitely has shining moments, especially in the slice-of-life scenes and some of the dialogue. It certainly could be very compelling once you get into it. But the last few episodes really broke the deal for me. The resolutions were awkward and hurried. And, as discussed in detail above, I just disagree with the direction the writer chose to take, both plotwise and characterwise.