who’s the guy with the brown hair i’m so lost

i think just someone that followed yujin home? he might have connections to someone who wants to hurt or WANTS yujin, he also could be doing a ransom thing where he kidnaps yujin and then requests money from aaron in return for yujin (i also could have just forgot if he showed up in other chapters..)

He's the gangster idiot moron that Yujin made a fool of in the bar when he was trying to hit on the bartender a couple chaps ago