I'n only writing this after reading lots of reviews that bash some of the plot choices they chose to make in the drama. I think the direction of the story and character development is partly misunderstood by most people. I do share some opinions but i want to lay out other possible meanings.

The story feels quite purposely made to be open to interpretation, but it also explains a lot about the characters in a way that it's not directly conveyed, but rather "alluded" unto, and it can easily be missed depending on how you take it. Let's tackle different points.

Yuno's victims: it's easy to question why did his victims ever go to meet a stranger that they knew absolutely nothing about. Yet this does happen in real life. Hell, even i am guilty of this. So it's not that unbelievable. Besides, Yuno might have tried to lure other people that were not shown maybe because his tactics failed and they were smart enough not to pursue him, so they never fell to be his victims. Maybe they only showed us the women he succeeded into luring, and coincidentally, only the women that were lonely and horny enough to take such a risk.

Yuno's backstory: this is most commonly misunderstood as something that was not dwelved into enough, and while it's true, they actually gave us important information during a scene where the bestfriend trio was talking about how mentally deranged individuals work. They talked about childhood trauma being closely connected to one's mental health and such, but they also said that some people just never want to change, be it traumatic childhood or not. This could very well be our peak into Yuno's past. We know his mother abandoned him, but that can be the reason he became a sociopath as well as a fruitless detail, as we know too little to establish if it was traumatic enough. Maybe Yuno was born with sociopathic tendencies that were only accelerated by certain things happening such as his mother's abandonment, or the first time he's shown killing a woman by choking her during sex. Maybe his mom abandoned him exactly because she feared being around her son, so it was not a trauma induced disorder at all. Or maybe his mom (or dad) absolutely abused the shit out of him and they made him be what he is (was) today. Could be any of these.

Gieun: this is the one thing i agree with as her being dumb asf. I just kept forgetting that she was a cop because she made choices so dumb i hardly believe anyone would make, let alone a cop, such as the second encounter with Yuno. She really thought she did something when she showed up the second time alone in her scary wheelchair, ready to confront the very same FLEXIBLE man that let her out to die. Great thinking. I couldn't empathize with her.

Shaman lesbian: while i get that that was thrown into the plot randomly, i feel like it adds to the realism of the show. It shows that people have unconventional upbringings, it makes it feel less "planned", if it makes sense? Just like real people. She goes out clubbing, she goes with many women, she is dedicated to her shaman lifestyle be it for family reasons or whatev, that's fine. This is a character that has a life outside of her usefulness to the main story. That alone deepens her character. I felt like the very fact that she was a lesbian but opposingly also a shaman, showed her character well.

Besides these misunderstood points, i can only criticize some of the dialogue. I get it - it's made to be driven by silence. Subtlety in the acting, in their expressions. Even selfinterpretation. But sometimes i feel like they overdid this side, only to take a lot from the dialogue, leaving it almost superficial and nonsensical at times.

But again, this can also be interpreted as it being intentional. Yuno and Kim Sum fell in love not over talking for hours and hours about all kinds of things, but over saying only what is necessary, and most importantly, they fell in love over recognizing their similarities and shared needs. They needed each other for what they lacked and what they had. They needed each other because they were both alone, because they were both misunderstood by the rest of the world. It's something deeper than saying "its unrealistic how they fell in love, they barely even talked."

Overall, i think this was a fine drama. The actors showed impeccable acting, as the acting was what held this drama up. The ost had some memorable moments for me, like when they played that beautiful cover of Scarborough fair. I liked how they managed to fit that song into a sadder, more grim rendition.
My score is not a 10 because of the poor dialogue in certain parts (where it was needed) and the weird ass blunder by Gieun. And also because i did not think it was THAT great of a story.

Thank you for reading my take on it.