Although this isn't the PERFECT drama, there are some things worth mentioning that do make this a rewatchable drama (in my honest opinion).

To start off, this drama is a rewatch drama- meaning, you need to hate it half way, drop it, and then pick it back up from the beginning to understand what the hell is going on. Other dramas I can categorize as 'rewatch dramas' are Oh My Venus, and Oh My Ghost (I didn't plan for them to both start with Oh My.)

Goods:
>Suzy's character, Noh Eul has the best determination I have ever seen in a character. Even though she herself has some very down moments, she still picks herself up, and that is what made me love her character. Most people are hypocritical with Suzy's acting and I do agree that it is bad at times but I honestly feel like she brought this character to life the best she could. She has no parents anymore, is struggling with her brother and her fiend from HS is now a popstar. Wouldn't that be your worst nightmare? If I figured out that someone that was an ass to me in HS was a celebrity I would honestly be pissed.
> Speaking of Joon Yeong's fame- I feel like it was almost needed in this film. It was a little useless in the beginning but towards the end of the drama, he had a lot of connections due to his fame that helped him accomplish his revenge the best way possible.
>The backstory between them is very meticulous and was actually all over the place, but a lot of backstories that have past childhood friendships/relationships are very mushy or are just put in the story line too fast. I feel like the backstory here helped the story when it was getting boring, and gave them such a closer bond. Almost like the bond you see in the drama Bubblegum (which is one of my favorite other dramas of all time.)
>I love the fact that they were there for each other. In times of Noh Eul's deepest sorrows and hardest moments as she complained and screamed with a bottle of soju in her hands, Joon Yeong experienced empathy for her and wanted to be with her with everything. At the same time, his character did a lot of pulling back- which I can only put to as him not wanting to get close to her since his impending doom of cancer slowly killing him. But, at his last waking moments- I really loved his character. With all my heart I did. He poured all his heart (the character and the actor) into getting a hold of his mom again throughout the drama, and you can hear his desperate pleading towards the end. The scene will stick with me forever because it seemed so real. He did SUCH a great job with his character.

The 'Oh My God GET OFF OF MY SCREEN' bads:
>Why THE HELL did the rich family even have to be in this? Why? Every second that rich family that is practically connected to EVERYTHING have to show up. They were bratty, and the one teenage girl was a legit brat when it came to her fangirling obsession with Joon Yeong like stop it, seriously. She made me not want to even watch the drama at times.
>Im Joo Hwan. I've discussed in my Oh My Ghost review how much I hate his character and how I never will like him in any drama. He legit ruined this drama for me in a way. I loved the two main characters and Go Na Ri. If it focused more on the relationship between the two of them and less on Im Joo Hwan's character- I would've rated it all 10 stars. Gosh. Pleh. Anyway.