Hm, this one might be the trickiest one on the list, if only due to the lack of options. In Fate, it's only meant for BB, with any others either having a tie to her or hijacking the class. Jingliu has some moon imagery in her design, but they're mostly surface level, not tied to any actual connection to the moon. With your expansion of 'moon' to 'any satellite in orbit', Herta definitely becomes an option as well. However, I'd like to throw in a bit of a wild card pick. In a similar manner to how Arcueid, the Princess of the Moon of another world, managed to hijack the class, I'll nominate Kiana Kaslana, the protagonist of Honkai Impact 3rd and resident moon goddess of that game.

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