
If she's supposed to die by the OG ML's hand because of the revival magic, why does she think she can have Nau kill her beforehand? Wouldn't he just not be able to?

Well before she didn't know about revival magic until later on, so she thought maybe nau can kill her before her brother does, but because kersten told her about the revival magic he casted that messed up her plans since now only her brother no matter what has to kill her and she has to loop back everytime unless the magic that was casted would disappear.

I actually kind of like that they didn't end up together (at least for now, maybe in the side stories they will) but the fact that even though she fell in love with him, she still stuck with her main goal of betraying him to escape. Sometimes manwhas derail once the mc falls in love but I'm glad this one didn't, because even if she did kill that piece of shit, she doesn't deserve to be in jail!
Garam has some serious trauma around "straight" guys and while Jaehyuk has been trying as of late to be a boyfriend to Garam, he has said a lot of homophobic things to Garam in the past and also had used him as a "human dildo". It doesn't surprise me Garam hasn't truly accepted Jaehyuk's affections or let down all his walls. But I do think Garam should communicate a bit better with where he's at emotionally, even if he doesn't go fully into why right now, just a little something so Jaehyuk can understand some of his boundaries.
Communication is key