He didn't even do anything this time, he had a "!?" speech bubble, so he himself was surprised when Haneul tripped on his foot.
Girl please, I can’t show you a photo because the website doesn’t allow it, but go to page 42 and you can clearly see how Jaeyeon makes him trip (don’t even try to tell me it’s the main character’s feet because there are two different sandals in that scene ). Even if he didn’t do it on purpose, he couldn’t even apologize, they had to drag him to make him say sorry and he looked like he was being forced to eat shit. Plus, putting that aside, everything Jaeyeon’s done in the previous chapters has been super annoying, not to mention all the pranks he’s pulled on the MC in the past (he literally enlisted him in the army before he even wanted to go, like who does that?).
1) Not a girl
2) Yeah, Jaeyeon doesn't stand Haneul, but the speech bubble clearly shows he's suprised that Haneul tripped.
Jaeyeon is so annoying and unbearable. His hatred toward the MC stopped being funny a long time ago, now it’s just irritating. Like, can you chill for a second and stop picking fights? If you’re so jealous, just go and confess already. It’s not Haneul’s fault you’re an insecure mess who doesn’t have the guts to tell the girl you like how you feel. It’s so stupid of him to take it out on the protagonist just because the girl he’s into is interested in the MC. Grow up man, there are more important things in life.