I mean they were just highschoolers, I think they needed the time apart to grow and be really sure of their feelings. I mean Lin Tian-Yu (senior) did try to explain to xu ze but I think xu ze was a bit emotionally immature to be like ok just because he is going to study abroad doesn't mean we can't try to see how this works. I think Lin Tian-Yu waited last minute because he didn't want to hurt Xu Ze's feelings but we all know that back fired. Like I said though you have to keep in mind they were only in high school which we all know high school relationships are hard to maintain because you are still going maturity wise and emotional wise.
KINDA SPOILER BUT I JUST WANNA RANT ABOUT
HOW MUCH I HATE THE DAMN TIME SKIP, THREE GODDAMN YEARS HUHH???? THAT SENIOR KNEW HE ALSO LIKED XU ZE BEFORE GOING ABOARD SO WHY COULDNT HE HAVE STAYED????? AND XU ZE SHOULDNT HAVE HUNG UP, LIKE HE COULDVE CONVINCED HIM TO STAY CAUSE LIKE THAT SENIOR WAS HESITATING BUT XU ZE HUNG UP LIKE WHY? WAS IT UR DAMN PRIDE? I KNOW THE SENIOR WAS A JACKAZZ FOR NOT TELLING XU ZE UNTIL THE GODDAMN LAST MINUTE BUT MAN XU ZE U COULDVE CONVINCED HIM SHSHSHHSHSHAHAHAHAHWB AND AFTER 3 YEARS HE COMES BACK LMAO EXPECTING WHAT HUH? I KNOW XU ZE PROBABLY STILL HAS FEELINGS FOR THE SENIOR BUT MAN U CANT JUST RANDOMLY WALK OUT OF SOMEONE’S LIFE WITHOUT TELLING THEM AND THEN COME BACK EXPECTING THAT THEY STILL LIKE U AND THEY WILL FORGIVE U, all said I’m so close to dropping this but I wanna see how their relationship progresses now since this time it’s the senior taking the lead