That highschooler is actually half brother of Hajin in the novel. He's the one supposed to be name Hajin but bcs he's always sick and need to be hospitalized constantly his position a go taken by Hajin in the novel. He's actually older than Hajin, but bcs he's always sick back then now he can finally catch up to his studies. That's why the mom's is so obsessed with the "high schooler" more as he's probably the son she has with someone she loves lol. The old man I can assumed it related to how Seonwoo? (I can't remember name) finally getting reveal he's actually from a rich family like in the novel
Wahhh. Now i get it! Thank you Akane!!
Can anyone explain what happen in the manhwa? Who is real hajin? Who is that high schooler? Why is the mom like that? Who is that old man? Im clueless