So Red's attitude is a wall she puts up to guard against her fear of being abandoned. Seems she's grown attached to Black-hair and doesn't want to get emotionally hurt. Hopefully no NTR with the brunette being introduced. I know how much manhwa authors love that shit.
@celedith thanks for another update and your continued work on this project. I’m really liking this story so far! Like others have said, hopefully no NTR. Really want Hayoon to be able to realize that her feelings are actually mutual and if she just opens up she won’t be abandoned.