Title 6/10

The title is so regret-ish. I don't have a problem with that, since your main goal is to show the POV's regret. But is it connected with the whole shot? I'd like to say a no. Maybe I'll explain it on the other components.

D&F 8/10

I would like to give a comment on the quote you have, "Let's break up..." then you placed a heart after it. Reading it, it's like... because of the heart, the feelings became postive. Like, readers are expected to get thrilled reading that. Since your fic is somewhat supposed to be a sad fic, you should at least attract them with sad emotions. 

Having some prologue is good as well for a oneshot. It serves as a preview and at the same time convinience to the readers since if you added it on the last chapter, they'd get tired reading a whole bunch of letters :)

Plot 10/15

A oneshot doesn't have to have a very complicated plot, so the plot met the right standards. But the plot is really confusing. Questions kept on playing, Why did Yukwon break up with Jiho and stuffs. I don't know if it's just me that can't comprehend, but I read it thrice already and I can't find the answer. The plot is simply all about Yukwon's regrets, which are really UNCLEAR. Why is he breaking up anyway, if he clearly loves Jiho? It has not to be too detailed, but it's really confusing, and the confusion drives my emotion more than dwelling on the sad part. 

It's actually not Too Late to Regret, because yes, Yukwon regrets but it's not fully regret because he's still capable of changing the situation.

Grammar and Spelling 13/15

I cannot list them down (the corrections) one by one, but you can focus on these:

• correct use of punctuations
• mispells
• specifications of pronouns

With the third one, I mean you need to specify clearer who are you reffering with "He". This is a common mistake when writing . 

Story Flow 10/15

As I said, it's a bit confusing, if I were to focus on the story and not on the emotions. Sorry I get a hard time reviewing using my old rubrics :)) 

Originality 12/15

It's not new, but not that used too. I'd give extra points here tho. 

Reader's Feedback - 10/10

They like it, and I often use this category to give the authors some extra points ^^ At least the readers get to enjoy the story (in a sad way ;A;). 

Note:

Sorry if this took SO LONG! Sorry sorry, school just started and I didn't get to upload this review on time. Sorry :(