Avoiding spoilers and just giving advice, the thing to keep in mind when reading this story is that Liz is not secretly evil. The premise is that Alicia is trying to make herself into a living contrast with an otome game heroine, so if Liz was secretly not that character it would undermine the point of the story.
The problem is that life is not an otome game but Liz is not acknowledging that, but people are getting caught up in her worldview even though it obviously makes no sense.
So yes, it's fine to hate Liz, just try not to assume she's an evil slut trying to make a reverse harem or anything. The problem is that she's exactly what she was written to be: An extremely intelligent and charismatic young woman with dangerously naive beliefs that typically go unchallenged.