kpop manga on dynasty is a honeypot to find minors to ban
There are 20 and 30 year old kpop fans? 2nd and 3rd gen fans tend to be older.
Since I used to follow kpop a lot and I read a fair amount of manhwa I didn't even realize that "unnie" was a weird thing to show up till I got to the notes and was like "oh yeah, they say oneechan in Japanese", like my brain fully didn't recognize the incongruity.
Also, yeah, Haneul/Solar definitely felt kind of manipulative. There's no way that A) she didn't purposefully get herself to Natsuki's place by pretending she's more drunk than she is, although the throwing up threw me off, and B) she doesn't know Natsuki is a fan of hers.