I think they are fully related siblings. The new Queen probably took over mother role since their mother died when they were really young. I wouldn’t be surprised if she poisoned their mother to become queen. So Marianne probably thought foul play was at hand for her mother’s death & resented the new queen & thinks that her brother betrayed her & their mother.
I hate her brother so fooking much. I know he's actions a reasonable but I just fooking hate his guts. I hate looking at him, I wanna put him in a hydraulic press. I hate brothers like that ugh
Lol ikr, he is so wishy washy. He’s being nice to her & then on the bad guy side. He may switch up in the middle & betray the queen. The queens son is an airhead & would probably ruin the empire. (〜￣△￣)〜
It's irritating that I can't read the bastard brother's intentions or emotions like did he really betray Marianne? Or are they really just half siblings? Or maybe it's that trope where the brother despises the sister because he thinks it's his younger sister's fault their mother died...
So this is what other characters feel when they can't read the other person
Anyways I'm probably gonna read some spoilers