I SO do not like Dahye. Yeonhwa is a psycho, I do admit it, but she is one too. The diffe...

Yeah, I both agree and disagree. I mean, I don't like Dahye as well. There were moments in a prequel when I could sympathise with her, but usually they were shut down almost immediately by some of Dahye's actions and behaviour that I found just unbearable. To be fair, I don't like or relate to any of these characters, just like in WAHNW and it's just really interesting to be still invested in stories full of mostly unlikable antagonists. But I digress,,
You are right, Dahye is a hypocrite - she definitely views herself above not just Yeonhwa, but in general she has a tendency to treat people like puppets. And I'm not trying to portray her as this evil and unscrupulous manipulator with zero moral boundaries, but she definitely has problems with a way she treats and thinks of other people. The only think I will give to Dahye tho is that, in comparison to Yeonhwa, she never went as far as sexually assaulting people, although you can of course argue that her current behaviour overshadows this one difference between these two characters. Cause, of course, it's not like she "imprisoned" Yeonhwa and has full control over her against her will, but on the other hand, she's been slowly ruining her (and not just her) life to the point Yeonhwa could easily be taken advantage of. Although again - you can argue that her "right" to revenge justifies her actions, but that's another topic I think
Also, a lot of it depends on how Yeonhwa feels about their current situation - how much of it was just her really not having a choice and simply being used by Dahye and how much of it is her being secretly alright with how things are between them, including the fact that now they live together. I think that in this situation getting Yeonhwa perspective is crucial, cause from this one thing it depends how bad some fo Dahye's actions can be viewed

Yeah I'm waiting to read when the author will write about what Yeonhwa is feeling about this

To be fair there is not enough info or content for us to figure out whats going on because it seemed like yeon was enjoying it but she still loves her gf and that was her home, now that she lost that. its high chance she reverts to her former self but it seems dahye also genuinely enjoys the pleasure. Maybe her sister becomes one of her weaknesses idk ik her sister helped dahye who lied to her own sister manipulating her etc. Everyone thinks yeon is at the wrong but she only protected her crush to be fair , dahye could of never bullied anyone and she wouldnt have been in the situation she was in. She will probably escalate her behavior and yeon is going to break gg.