Title : (7/10)

Since it has only one chapter,I don't actually know the overall plot,sure you say they're strange,but there isn't any points in the first chapter that proves that they're peculiar,except for the fact that they do everything in unison,I give 5 points to that. But the title do catches the readers' attention,it isn't in a dull vocabulary neither does the title seem plain,so 2 points for that!

Description&Foreword : (5/10)

Alot of writers tend to leave their forewords for the authors' note. No. Forewords are suppose to be a section where you kind of insert a small segment of your story so that it lures the readers to keep on reading. The description was okay and I give 5 points to that. Or if you don't want to inset a small segment of your story you can maybe explain more about the main characters,like Sungmin and Minchan maybe? Because short forewords tend to not catch readers' attention,well in my opinion that's what I think.

Grammar&Language : (13/20)

Your grammar and language was quite okay,average but there could be more improvements,like you can write them in a better way or so,so that it can look nice and I did find some mistakes though,but no spelling error,which was good! Like this sentence,it could be misunderstood by alot of readers since you didn't actually format it properly, "I would have complained if we were back in the city but the town was so nice that it seemed walked to school is such a fun thing to do,alone or not."

The first part of the sentence sounded quite okay,but I guess the last part,you actually meant, "But the town was so nice that walking to school seemed like a fun thing to do,alone or not." Doesn't that sound nicer? Hehe,so I guess you have to take note on how you put the words so that readers will understand what you're trying to say!

And another one, "137,137,137..." I chanted as I looked for the mentioned room." For this sentence,I replaced 'said' with 'mentioned',because it seems nicer,but since English isn't your first language,you wouldn't know,but it's okay,you can learn from your mistakes. ^^ As I said before,your story isn't that bad,but there is quite a big room for improvement!

"Just sit somewhere there and wait for the teacher. The bell is going to ring soon."

"I turned around,wanting to greet her and thank her,and maybe ask for her name too,but when I did,she vanished."

"We ate the sandwiches whch our grandmother made in silence,and when the bell rang,we followed the other students to the gym." I removed some unnecessary coma(s) if you have noticed. The coma between 'sandwiches' and 'which' was kind of not needed,so as the coma between 'made' and 'in'.

"She crossed her arms and pouted. "What should we do?" " Even though 'what to do' sounds a little inappropriate,you still used it in a wrong situation. Usually when people used 'what to do',they usually use it when they are in trouble and they ask for a solution,or something like that,or maybe it's just me cause I live in Singapore,a country full of English like this,LOL SORRY.

Characters : (14/20)

Okay split it in half,7 points for Sungmin and 7 points for Minchan. Both of them do not have enough elaboration,since it's just the first chapter,this is the only mark I can give you,sorry. But based on the first chapter,both of them did not have enough elaboration on their character traits and their personality,but the reason why I gave 7 points to both Sungmin and Minchan is because I can only get a quarter of their personality.

For Sungmin,I could tell he was a hardworking guy,I don't know how,but he sure sounded hardworking because it seemed that he liked going to school,oh,and he reads books! Usually high school students in fanfics doesn't read books unless they were defined as nerds,which I find it cool that you made Sungmin read a book and NOT define him as a nerd at the same time.

For Minchan,she was quite a playful lass? She was gleeful and happy most of the time and out of all the places she chose to poke,she chose to poke Sungmin's side(I take it as the ribs at the side,where you funny bone is),even though it's a minor action,it tells the character's personality well. I find it quite cute though. So yeah! 7 points for both!

Flow of story : (10/10)

Perfect score! Because at the moment,there's no point where it's actually that fast and that slow,everything's balanced perfectly and good job for that! I have said it in my first review that it's quite hard to pace everything equally(or maybe not) but yea,so 10 points for that!

Originality&Storyline : (7/10)

Out of all the horror fanfics(or maybe mystery) I've read,yours a first,I think. Although I don't really know the overall plot on how peculiar the Cho twins are,the first chapter really sounds unique(or maybe the beginning to something unique),it's still a good start and this is the only point I could give you because it's just the start of the story. But I liked how you described the vanishing girl,it's quite simple,but still good.

Overall : (56/80)

The first chapter sounds kind of interesting and it sure gives off the mysterious feels and creepiness,everytime I read about the vanishing girl I just imagined her popping up in Sungmin's face like a screamer(had a bad first experience for a screamer,LOL) and hows,please update soon,so maybe I can get the overall plot of your story. Learn from your mistakes and maybe improve more on your words and how you formar them! Remember to credit the shop in your foreword so I can cancel your name,once again,thank you for requesting at KMS & HMH Review Shop! Have a nice day~