Siru is a delightful protagonist: she's funny, amiable, not too smart to be challenged and not so stupid she's infuriating. She's open with her feelings and just a smidge oblivious to the feelings of others, which is an entertaining combination at times.
Gibaek is extremely frustrating. I understand that many a young adult may act the way he does, and at the same time I don't get the sense that his behavior was concordant with how Siru and her other friends understood Gibaek or how they befriended him. I'm not convinced that the writing is strong enough to make his actions believable or make sense.
Nonetheless, he's only even really around for season 1. Thereafter he becomes (to date) completely irrelevant, so I'm not too excited about the summary and thumbnail art on Webtoon featuring him so prominently. That suggests to me that the story was drafted only up until the point that Gibaek was involved, and we are now flying by the seat of our pants, which never goes well.
Cheol is delightful. He's taciturn but honest, hard to read but funny, and stalwart in the face of all the drama that happens around him. I know this is primarily a drama so it's silly of me to be put off by how dramatic his "backstory" is, and yet somehow I still am. Cheol's interpersonal conflicts make absolutely no sense, perhaps on purpose because the authors don't want to reveal it yet to heighten the emotional turmoil, but all I end up feeling is perplexed and frustrated by the implausible extremes that seem to be on display here, not curious.
The art is very pleasant and clean to me, and I enjoy it a lot. I do think that sometimes the eyes, especially Cheol's, are a little too heavily stylized for my taste, but then I remind myself that this is (essentially) the medium of Tanemura Arina and I can go stuff my opinions.
All in all, an enjoyable, attractive read. The writing could be stronger, particularly where it sacrifices grounding for dramatics when the two don't have to be mutually exclusive. At the same time, we're not breaking new ground or anything here.