People may change due to their surroundings and perspectives in life. At first he was a kind boy, and after that something changed. What exactly changed? Wanting to have money and having debts instead? Well it is a good possibility. Being surrounded by these classical Korean dudes? For sure, that would be aswell.
From my point of view, you're right, but they are not giving you the exact reason. They are showing you the character in his environment and you can take your own conclusions.
The story has taken the most traditional point of view, that is... Women should be submissive (and with that... All the waiting at home and cook and be ready to have sex).
I don't particularly like the way the story is going, I would like to wait for more chapters, because I think mincheol will react as an aggressive guy if he finds "he's not the only dude who can contact and fuck her" and.. well, you know, not something everyone wants to see in their daily lives. Also, he will end up making her feel even more worthless.
Still, I hope for a bright future for her:D
lmao and we know he's gonna find out she's already had someone else and he's gonna get his karma or smt like that.
y'know what, I'm starting to think about it in a more general or broader perspective. Mincheol used to be so different, a sweet guy who loves his girl, but still he turns into this trash. This is just proof that anyone can become ... anyone. In this case, Mincheol seems to be affected mostly by his colleges and bosses in his workplace, and he always seems so eager to prove himself because he always feels inferior, lesser person in society. Now idk if the story is trying to say that, but it could very well be in my opinion.