I do wonder if the FL character's name is the author's best attempt at writing "Citrœn Balmoral?"
I haven't checked the raws, and I'm only at MTL level of translation, so I obviously wouldnt know for sure, but...
It really feels like the name of a real gemstone, and then the name of a real Royal castle, would be an obvious choice for the mangaka to use for a fictional Royal princess, right?
And those words would be nearly impossible to write in Kanjis, Hirigana, or even Hepburn/Romaji, so the spelling in Japanese/日本語 would be... well, phonetic, at best; at worst, it would be nigh-on illegible.
So, I would support her name to very likely be "Citrœn Balmoral," and be of the Balmoral Family.
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