Granted he was unable to understand Ahjashi's perspective, yoo il was indeed the victim. Ahjashi tracked his location and his calender, then made plans ON PURPOSE on the same day as yoo il's uni trip, AND THEN PROCEEDED TO LIE ABOUT IT LIKE AW I DIDN'T KNOW CUZ YOU DIDN'T TELL ME and guittiped him into coming. If he was such an understanding adult, he wouldn't do such things. He was gaslighting him too when he was confronted about the location tracker. He would hardly ever be the first to contact Yoo il yet still wait for him to text/call first (until the part near their breakup).
I can excuse not wanting to show pda in public or take pictures together, that just hurt the kid a bit but it wasn't the main problem.
Ahjashi was even surprised when yoo il said he had told his friends about having a girlfriend (Ahjashi), like how much do you want to keep a secret? The man should at least be able to tell others that he is taken.
Def deserved to be dumped but I simply cannot condone thw violent throwing of Ahjashi onto the sofa and the collar grabbing. That was a bit much.
But he did. He confronted him about the tracker, asked for an excuse that could properly explain and give a reason for such actions. Ahjashi did not give any. He couldn't. There is no reasonable justification for what he did, it was completely unprovoked. After this Yoo il was able to take a proper look at the relationship and understand how toxic it was, yet he still liked him so was sort of willing to give him another chance (ish). Only to find out he was a replacement for his father and that was the last straw.
kinda mad at Yo Il. Ahjussi was trying not to get involved with him but he kept pursuing Ahjusii. Ahjussi wasn't able to convey his thoughts that well because of the fact, his life-long regret in the past. Yo Il should've gave the chance to at least talk or break it off with Ahjusi, nicely. He came into his life but left, too painful for the other to bear. I hate when ukes are like that, repulsed by emotions. Though, the relationship was toxic but at least don't cut off people like that, Yo Il was OLD ENOUGH (this manga doesn't fall into the pedophilia scale), you don't understand what you've already impacted on that person and if you leave suddenly, that won't make you a victim.