Title: 4/10
Honestly the title is not very unique, nor does it fit your story. Upon reading your first page, I assumed that the story would be about Daehyun trying to win Youngjae back after losing him. However, as the story progresses, it feels very much like it is a stalker fiction in which someone is going to end up dead. If your aim is for the romantice story, there are some changes to be made. If your aim is for the stalker fic, then your title needs to change.

Plot: 10/35

                1/5: Originality
                I have seen a lot of stories about break-ups and going to get married and deciding to get back to the person they love instead. There was nothing really original about this story. Sometimes that is not a bad thing, because in my opinion, all stories have been told before. It's just a matter of how well we tell them to make them feel new again. This one needs some work on deepening the characters and the setting to make it feel like something new, otherwise it is just the same story I have read again and again.

                2/10: Believability
                I know that you were aiming for Youngjae to be the delicate, love-struck boy and Daehyun the possessive, strong man. But honestly, it isn't working. Honestly is creepy that Daehyun just stalks him, following him around and taking pictures of him. It's not really the behavior of someone trying to win their ex back. Also, Youngjae acting so paranoid and violent is not how people act when seeing their ex, especially when it was a simple 'It's over' break up and not with anything to make him so afraid of Daehyun. It's not logical.
As for Youngjae getting beaten up. Unless it was by Daehyun and some thug, it was unnecessary for the story and really felt cliche, like something out of one of those soap opera dramas. What happens in manga and dramas is not how things happen in real life. If these two were so in love before, then why are they acting as they are now??

                2/10: Narration
                Your narration is very stilted, mainly because you work off of conversations between your characters instead of showing the reader what is going on. For instance....

                5/10: Setting
                ... As a reader, I have no idea where the story is taking place, what Youngjae's home looks like, what he or Daehyun look like, anything! When writing a story, never rely on people's previous knowledge to picture your character. They are YOUR character. So describe them, as well as the area around them. For example,
                Brushing his dark hair out of his eyes, Youngjae hefted the grocery bags and started his journey up the stairs. He lived on the third floor of the apartment complex, in a small two bedroom unit that he shared w