First of all, the art is absolutely stellar. Second, this is a short story where the narrator/MC is unreliable. Her perspective leaves out huge plot points which are revealed at the end, but it changes the entire meaning of the plot. By the end of the story, none of the characters really felt likeable and the way everything settled felt underwhelming. Now for a bit of spoilers and my explanation as to why I rated the way I did (TLDR at the bottom):
MC's attempt at "atonement" by prostituting herself and blaming others left a really... sour taste in my mouth. I don't see how her doing this makes up for the fact that 1) she got together with Sehyun because she couldn't become lovers with Hyun (Sehyun's older brother), 2) she cheated on Sehyun with Hyun while they dated, 3) openly admitted to herself that she just wants Sehyun's love as she one-sidedly loves Hyun, 4) she gets pregnant (I'm not sure if it was a false pregnancy or what, because she says this twice in the story and nothing really happens of it).
Yi Hwan and Han Yul got off pretty easily, but I guess it fits the story because of the chaebol backing, yada yada. They're both pretty bad people, Yi Hwan moreso, but there honestly isn't much to say about them. The ending for Han Yul is meh, he basically gets ruled as innocent, gets away with murder, and his career continues to flourish. Yi Hwan... he's kinda just a hot mess that gives off a slight yandere vibe. He shows up at MC's doorstep at the end which... what the hell.
Hyun is the real rotten character of this story, truly a garbage dude. He takes his younger brother to a chaebol party and sends off his brother before indulging in women, drugs, and alcohol with Yi Hwan. The issue is Sehyun turned back to see the party, and instead witnesses his perfect role-model brother in an orgy. Fun stuff. Hyun gets pissed and says he wants to talk to Sehyun, scene cuts out, and then we know nothing of what happened after that. After Sehyun's suicide, Hyun "helps" MC with her atonement (?? girl this is not how you atone...). He basically acts as if he has no idea why his brother died and the way he acts is just... really scummy (especially when he erases parts of Sehyun's suicide note/last text messages for MC). Unlike Yi Hwan and Han Yul, who will show their true colors, Hyun is not that type of character which I think makes him worse.
Lastly, although Sehyun is innocent here, his cause of death is on him. At first MC thought that Sehyun was murdered, then later found out he committed suicide and attributed it to seeing his older brother, Hyun, doing disreptuable things. The truth is that Sehyun committed suicide after finding out MC cheated (MC accidently sent a text about her pregnancy that was for Hyun to Sehyun). You can't fully blame MC because this is Sehyun's decision to commit suicide over his girlfriend's adultery. It's also important to note that Sehyun knew MC loved Hyun and not him. I think the pregnancy was the final blow, but I do think that MC can't be fully blamed for his death.
TLDR; everyone in this story is a god damn hot mess. The ending was underwhelming and so many plot points felt redundant or ignored. Art is fire tho.