Well, I think it has to do with the fact that, in another chapter, it showed either she confessed to someone or someone confessed to her. I understand the cultural differences, but they are also thought to respect their elders, and this is a show of disrespect.
Either way, she is old enough to know not to do that shit. Especially if she asked already, and he said no, so this is taking it a step too far.
I like the way they are approaching the subject, with communication, but I am also a little afraid that what she did will be glossed over, it is a precarious situation and I am in the "let's watch and see".

What about it??? The fuck that gotta do with you? Instead of just asking, you signed him up on dating websites. That’s some serious breach of privacy. Haebeom wasted his money for your study.