
Oooh ok I understood! So back when they where highschoolers, there WERE a bit something between them, thought they each hid it behind a « we’re just making out for fun lol ». As they each grew feelings, MC sees ML kissing someone in the class and gets heartbroken. BUT we can see on the kissing panel the moles are not the right ones, it’s ML’s twin! Who is wearing a wig apparently cause that’s not his hair color.
So then we get MC who thinks that the « we’re just making out for fun lol » was indeed for fun and no flirting, and he breaks things up with ML. Things happen, ML’s twin dies, years pass, and MC and ML met again. They both are « oh, my old crush who broke my heart by being interested in someone else/breaking up out of nowhere! I might have a chance this time! ».
But they are both idiots who won’t talk about « hey last time when we were in high school you did this I was sad. I had a crush on you it’s a bit embarrassing but YEARS HAVE PASSED SO I CAN TALK ABOUT IT ». So instead they feel anxious around each other and play a game of tag. So yeah, now I understand why ML thinks MC is weird with his boundaries.
Only mystery left is why the brother wore a wig and why he died. Was he jealous of ML and trying to pass as him to destroy his reputation?