Wait someone explain me. The black hair guy was declared brainded but woke up. The brown h...

The moment he woke up he doesn't have his memories. Also why the brown haired asked for break up is that I'm guessing because of the parents of black hair. They kept blaming him for the accident and why the black got into that state

And maybe also because of black hair situation, since he can't accept (from the panel he keeps denying his relationship with brown hair) so maybe that's also a factor that drove our brown haired mc to his decision to break up

it’s a little confusing!

ML loses his memories. MC tells ML guy of their relationship after ML wakes up from the accident but ML doesn’t believe him(ML is actually a little disgusted).

In the very first scene of chapter 1, it showed a scene that happened AFTER ML is made aware of that they dated.

MC decided to break up with ML(probably to “set him free”), but ML gets mad that MC is supposedly throwing away a “7 year relationship”. ML doesn’t remember this relationship, but is still visibly upset(probably because he thinks this implies ML never cared that much even though they were together for 7 years).

Aah got it. So then why is black haired guy (cha yun) upset with the break up? Since he anyways doesn't remember a thing.

Ok thankssss

Uhmm imagine this, you have a very close friend from childhood and you like them very much, but suddenly you lost your memory or something so you can't remember them, but the emotion that's already built-up are still there. So maybe the black hair is reacting to that emotion right now.

He's still unstable if you think about it, being in a coma and bad accident, then woke up with a different timeline, he'll be confused and specially if his mind is at that young age of 22

Sorry i also can't explain it in a better way, and I'm also not sure since i haven't read the novel yet. But if you scroll down the comment section some readers tried to explain it