The story of a civilization that flourished but then fell apart is one that repeats itself in the game's backstory, and that civilization is always a Lumen one. It is said that the first recorded Lumens came from Borealis, but that just means that they were the first magic-using people on record. No one knows what became of the ancient civilization of Jiavar, just that they vanished without a trace and left only their stone buildings. It's possible that there are no surviving records from that time, or that no one has been able to translate them. A disaster brought upon by magic might be the cause of the sudden fall of the old civilization.
If a magical society did exist in Jiavar, it would explain why the Shanjian Togami - a possible descendant - was able to bond with a crystal and perhaps explain where he got his crystal in the first place.
Lieke was said to have divorced Yannik soon after Gwenelle was born "to marry another," but it's never explicitly said to be Bennett that she married. Bennett was only thirteen or fourteen at the time of Gwenelle's birth, and Gwenelle says that he ran away from home when he was around her age (fifteen), which caused his mother to disown him, implying he was still living with his family at the time. Gwenelle also says that he spent time travelling the world, which is time that needs to be accounted for. It's not impossible that he was married to Lieke when all this happened, but it seems unlikely. Finally, their son together, Anciet, is only eight-going-on-nine, meaning that we only know for a fact that Lieke and Bennett have been involved for a little under a decade.
Lieke's second husband was probably someone unimportant to the plot or greater nobility, hence why he doesn't get a name.
- Not quite Jossed, but made less likely in late update to the game: the wording of the Internal Affairs lesson that talks about Lieke's marriage to Yannik is changed from "divorced him...in order to marry another" to "divorced him...in order to be free to marry another". Lieke could have still married someone unimportant in between Yannik and Bennett, but the rewording takes away the certainty of a marriage happening soon after Gwenelle's birth.
We're not told much about Elodie's taste in men/women besides that she thinks Kiran and Talarist are good-looking (and we don't even see Kiran). But at least four of her endgame options have them — Kevan, Ignatius, Briony, and the Earl of Pastry — and those are all endings with a "romantic" component. In the case of the last one, it's one of the only things we know about him aside from the baking.
- The baking is something he shares with Evrard, so she apparently also likes a man who can satisfy her sweet tooth.
Inspired by a bit of Fridge Horror I just had. His mother is the second most powerful woman in Nova, and if she becomes Elodie's mentor as an alternative to civil war (meaning Elodie's already on thin ice with her), she'll be at the tournament, meaning she'll actually see Elodie set her son on fire.note Estranged or not, that would be the last straw. With the low opinion most Novans have of Lumens and Elodie's growing reputation for cruelty, Arisse should have little trouble getting support for a second rebellion just as western Nova is still reeling from Shanjia's invasion, potentially tearing Nova apart.
- Kevan will only attack Elodie if Arisse or Briony is dead. If Elodie recruits Arisse at the birthday party, she mentions Briony's questions about the old capital and Arisse will promptly head them off at the pass whether or not Elodie knew what she was talking about. If civil war breaks out after the party and Briony hasn't gone with Elodie, she stays alive, possibly because all the turmoil keeps her from making it to the Old Forest. However, if civil war hasn't broken out because Arisse isn't quite that annoyed with Elodie yet, and Kevan goes off half-cocked over Briony, immolating him would be a very possible tipping point.
If Julianna is any indication, the House of Ursul takes its duty towards Nova and magic very seriously. It's possible Duke Paulus thought Julianna was better equipped to handle the ostracism that comes with openly being a Lumen and decided to leave his crystal and duchy to her. Alternatively, Ignatius made it clear that he didn't want to live as a social pariah by taking up his father's crystal, so his father denied him the duchy. Or maybe Julianna always showed more promise from the beginning and their father just decided to place his hopes in her instead of his disappointing elder son.
She has its Lumen crystal, but couldn't present it as proof of her lineage without blowing her secret. Her actions regarding Elodie are essentially revenge against Fidelia for not giving her the Mervan title, which is why she can be appeased by elevating her to a royal minister or giving her the title she wanted all along.
An alternative take of the above, in which Lucille did privately present the crystal to Fidelia as proof, even though it risked branding her with stigma. Fidelia might have realized the same thing and vowed to keep it a secret, but without revealing this information to the public, Lucille's claim had no foundation.
Fidelia chose to make a compromise. It would have been less trouble to appoint a landless former prince to the ducal seat, and while Lucille herself would only be a Duchess-Consort, her children would inherit and reinstate the old ducal bloodline of Merva. There could be any number of reasons that Lucille is displeased with this arrangement Speculation , but whatever the case it's built up to her coveting greater power.
One issue with this theory is that it's likely other characters should know about this too, but they apparently don't. Specifically, Julianna and Selene either don't know that Lucille is a Lumen — though they should be skilled enough to sense her — or else they do know but act as if they don't, even in urgent matters where they really should bring it up (gathering magic-users at the naval battle, Mervan threats on Elodie's life). It's possible that they're sympathetic to the plight of hidden Lumens and will keep it a secret even in dire situations, such as Julianna not outing Selene when discussing the naval battle or when preparing Elodie to go into hiding. That said, it's more likely that they would only go to such lengths for someone they love, and not for any unknown individual that happens to be a Lumen. They react swiftly to the strangler, after all. Julianna appears surprised when Elodie reveals Lucille's status, rather than the superior you-didn't-need-to-know way she is when Elodie reveals Selene.
Since Julianna is openly a Lumen, anyone trying to hide a secret crystal would know to keep their distance from her. Lucille would not know to avoid Selene, but as a non-noble priestess, it's likely they never crossed paths. But Fidelia was also openly a Lumen, and if Lucille was trying to keep her own secret, she could not have dared come too close to the Queen without being revealed. So did Fidelia know or didn't she?
Elodie's situation is very similar to Kelson's, as a child-ruler who has to rule after the sudden death of their reigning parent which was secretly caused by a hostile, ambitious foreign noble but also has to wait until they legally come of age and is almost killed multiple times before the official coronation. Their surviving parent acts as their regent and wants to protect them, but is adamantly against them learning magic, despite it being traditional and probably necessary for their survival. Another prominent adviser is the one noble who openly uses magic and acts as their tutor despite their parent's objections and personal dislike, and their teacher is close friends with a prominent member of the court clergy who is also secretly another magic-user with a secret relationship that makes them even closer. The kingdom the new monarch rules traditionally has a mage ruler while other magic users are persecuted, and one of their goals is to make magic and magic-users in general more accepted in society.