
I gotta say, Lee Hwa is quite an unlikable character.

I don't get this. What has she done wrong, aside from the initial disappearance? She's been respectful, given Hayoung all the space she's asked for, has even offered to literally be the bad guy if it helps Hayoung fit in and feel comfortable at club. She's shown nothing but empathy and concern for Hayoung and understanding towards her relationship with Seo Woo.
If it's the initial disappearance that is poisoning you against her, I'd be willing to wager we haven't seen the whole story there. The way she disappeared -and- cut her mom out of the picture suggests that her mom was not so cool with their relationship as she said she was. She probably threatened to contact Hayoung's parents if they didn't break up. Or her boyfriend did and she didn't intercede. Whatever happened, I'd bet real money Lee Hwa left to protect Hayoung somehow, and it destroyed her relationship with her mother. It's just speculation, but I definitely think there's something deeper there.
Wait, did mister mysterious guy draw the maze that main character girl is going through now into existence?