Yeah, while I'm not a fan of the amount of real estate the bullying is taking up this chapter pushed forward a ton of important things. Jiu-tae and Maria's interactions and the closeness and proximity, the small things Maria does when she looks at him, their complete comfort in being under the comforter together, it's establishing a very close-knit relationship between the two. Plus we got something incredibly important about Maria's past and about how she is today as a result.
Unfortunately because the manga was doing something important at the same time as dropping a pretty common trope (oh no, girl who is staying with me is here while childhood friend showed up, hide, oh man awkward circumstances!) it made Jiu-tae come off reeeeeeally shitty. Like, Maria is having a PTSD episode in the closet, his friend is trying to talk to him about their mutual friend being bullied and he's making faces and not paying attention. Not a good look.
Kinda shitty the friend makes excuses for Jiu-tae, she shouldn't have to do this herself and go "Oh well he's under a lot of pressure."