(Spoilers further down)
I finished this in a few days (3 or 4) and I really regret staying up to watch it and spending so much time. The premise of the drama itself is interesting. HOWEVER, the characters are not well written AT ALL. They make irrational decisions with no reasoning and none of them are held accountable. It makes no sense how people can do such senseless things and have no repercussions. I enjoyed the romance part but I almost couldn't watch parts because of how frustrated I was with certain characters and how their actions made ZERO sense.
SPOILERS BELOW
My first problem with this drama is that they present Hye-yeong and Sun-oh as best friends how truly care about each other. Then, when Hye-yeong makes it CLEAR that he likes Jojo, Sun-oh decides that he for some reason has to be with her. Why? Because she stared at him a few times and didn't have love alarm? Who knows. It makes no sense that someone would do that to their "best friend" who clearly has a major crush on someone. Even when they talk about it and agree they will tell her together, Sun-oh still goes and asks Jojo out himself. And Hye-yeong does nothing! Wtf? Does he not like her?
Next problem: Jojo's family. Her cousin is the WORST. And Jojo just allows her to do it. The thing that she holds over her head (that Jojo survived? and not her parents?) would not really hold any weight over Jojo in real life. She clearly did nothing wrong and was a very young kid so why is anything her fault? It's not, but they needed something in the story to make things hard for her.
Next problem: Hye-yeong was rejected by Jojo SO MANY TIMES. Why can't he just take no for an answer. Yeah, she kinda likes him, but in real life, people don't reject others that many times if they like them. He is being a creep.
BIGGEST PROBLEM: there was no reason at all for her to break up with Sun-oh. Yes she was going through a lot of stuff emotionally, but ? ? why? ? there is no real reason and I hate it.