I understand that this is ur opinion but I think the manhwa isnt normalizing adults for their big age gap when dating. The manhwa itself criticizes that subject and it handles it in a different perspective for other people to understand. It can only look terrible when the other party has ulterior motives. Im not against you, thats your opinion but I just want you to understand that the manhwa isnt normalizing it, it explains it :)
I think this is a pretty extreme perspective to take. I could understand if Yeoreum was 18-21 or if Hyeonseon was his boss or mentor. But that's not the case, in the story Yeoreum is a 24 year old working adult who meets Hyeonseon as his guitar instructor.
The issue with age gap relationships when it comes to people under 23 is that they're often immature, lack experience and don't know how to navigate relationship dynamics with an older adult without relying on that adult for guidance. This is not an issue with Yeoreum because he is an established adult with plenty of experience on his own. We see in the story exactly how capable he is of managing his own autonomy and relationships.
Ultimately some grown adults will enter in relationships with other grown adults who are significantly older/younger than them. As long as both are experienced, capable consenting adults who met as adults there should not be a problem.
Tl;dr let's not police how grown adults date please and thanks (signed, a man in his late 20s who prefers to date older people)

hey so overall the story is nice like it touches some heavy subjects in a very beautiful way but i cant overlook the fact that the age gap of 16 years is insane. i might drop it even though the story is nice because we shouldn’t normalize being in a relationship with someone almost half your age.
but yeah in the end is my opinion.