For a while I played a Keeper of the Moon who was so isolated in her youth that she didn't learn to read or write until adulthood. I figured that Miqo'te families living deep in the woods (especially those on poor terms with Gridania) would lack the educational resources that city-dwellers have access to. That was part of her backstory, though - I haven't tried to write a character who is illiterate in the present. I think I might find it frustrating, but that's just me.
Michaux Vidal - Oyuna Qestir - Tatsu Kaisuri
Arnvi Sunblade - Noriyasu Kuroda - Lucien Lemaire - Bren'li Arhys
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