Interesting
What are the character arcs about?
I'm gonna try and generalise as much as possible so I don't monopolise the chat
So Lysia's is the main one! As a 'daughter' of dusk, she's equally split between night and day/light and dark, and struggles greatly with resisting her darker instincts (that translate as intrusive thoughts). With Dorota, her anchor in sanity and control, gone, she loses her grip on her powers and especially because of Circe, she goes from a fragile control to completely losing herself in every dark instinct that, after having been repressed for so long, are out of control and powerful. Her arc is a sort of lesson in accepting every part of you and learning that the way you're born doesn't define who you are as a person sort of thing.
For Dorota, although she's an ultimately good person, she's caught up in thinking she's naturally superior to others, and she doesn't actually treat the people around her very well. This makes her very easy to control when the gods take her in, and leads to the battle at the end of the story. Because of how much she relies so heavily on the idea that she's more powerful than anyone, she doesnt realize how much damage she's doing, both actually physically and emotionally to her relationships as she fights them pretty ruthlessly. The consequences of the battle basically humble her, and she kind of snaps out of her attitude and realizes how important her relationships are to her and everyone around her.
Diego, once fully trusting and very optimistic, is kind of destroyed by losing first his sister and then one of his closest friends. His worldview was that love kind of runs the world, but seeing two people he loved try to kill each other kind of breaks all of that. He dies before he can fully proces everything though.
Yanni is a bit similar. As a leader/parent to Lysia and Dorota, losing them made her desperate to find them and help them. She's terrified at the idea of not being able to control her surroundings and believes that any consequence of Lysia and Dorota's feud would be her fault for not helping them. But when she finally finds them and tries her best to talk them down in vain, she realizes she can't do anything for them and can only protect herself from the damage they're causing. On the topic of emotional boundaries and taking responsibility for yourself before anyone else, I think. She's a bit complicated and I'm really trying to get my head around her thoughts and emotions.
Then you've got Kohmir. Similar to Lysia in having difficulty keeping his negative emotions in check, especially as the youngest character. But he's got a lot more self-control and enough self- validation and motivation, and is able to keep rational thoughts in situations in which Lysia would get more worked up. He greatly admires her though, and she's an inspiration to him. If she can make it, he can too. So, when she doesn't make it, he loses a lot of hope and loses progress he's made on himself. He's also very very close to Yanni, and seeing her so affected makes him really bitter towards Lysia and Dorota. So overall a lesson in self-reliance I think? Not only, there's also a lot about learning how you react to things, how much you can handle, when you come first and when other people come first. How do you protect yourself when protecting yourself means losing people you've learned to rely on?
Finally you've got Maitea, Lysia's love interest. So when she meets Lysia, the latter still has some semblance of control on herself. But Maitea, although very set on Midas's values and maintaining her loyalty to him, is watching from a distance as Circe absolutely destroys everything Lysia's internally built. Especially as her feelings for Lysia grow, she struggles between long standing arrangements and what she owes her love for Lysia and her own values.
That's what I've got so far!