
What's the age difference between them again? I mean it doesn't seem like light years apart but i could be wrong..

Nah, I don't think it is the amount of years they are apart so much as that our silent heart boy is a high schooler. How many college kids hang out with high schoolers, you know? I don't know about Korea and age gaps with minors. But they are pretty much like the West when it comes to age gaps between adults.

Seeing all the comments that it might be a trap i hope it's not true. I need their reunion!

WAAAAAAIIIITTTTT....
What flashback? Why can't I remember?

In the very start of the manga they are older.
The flashback start a bit after this chapter --> http://www.mangago.zone/read-manga/19_days/bt/311115/Ch45/1/
Haha that kick! Goodjob Siwon! XD but boo to the repeat of chapter 27 in chapter 28:/