havent read shit yet but i already know this is going to be messed up from the a year apar...

Probs the twins being born on the last day of the Korean school year and the day around midnight if I have that right. Or, I think new years and new years eve because traditionally Koreans age 1 year on new years while still celebrating their birthday.

yeah that could be it do they ever mention it?

I don't think they do because Koreans (author's target audience) should generally know about twin birthdays and such. Also, if they were born between school years, then they would only be one year apart in the sense of what year they are in at school. And, either way, they are still minutes or more apart in physical age.

Uh they're twins?

I've read until chapter 18 years ago and i always thought they're simply brothers, not twins? Did i misunderstand something?

it says they're twins in the first ch page 10

Okay i'll check it

Okay i think i get my memory back since it's been years, i thought that "twins" is only a metaphor because they really look alike

thought so too but turns out theyre actually twins

Yeah, it's just that Koreans and probs other Asians do birthdays and counting age differently.

i dont really understand sorry could u elaborate on the between school years thing?

I forgot a lot about this webtoon, i only checked the first chapter, so is the older twin a sunbae?

Korean school year started on march, the oldest korean student in their grade is also born on march... If these twins are 19 and 18 years old, the only possibility is being born on december 31st and january 1st, so there's no way they were born between school years (because korean school year is set on march), and they should be in the same grade, unless the younger twin failed a grade

Only koreans count age differently

Other asians even japanese count their age normally, we're considered older in our birthday date (korean is immediately older in new year start), and we get our first birthday a year after we were born (while korean babies are considered 2 years old in just a year after they were born)

I understand japanese school year better than korean's

In japan, school year is set on april 1st, you must enter elementary school if you're already 6 years old on april 1st, so children who were born in april 2nd can't enter (they enter school next year when they're almost 7)

So if japanese twins are born in april 1st and april 2nd, they will be in different grade in school because they were born between school years)

Korean school year started on march, but idk what date