I think that translating the Japanese name of the café was probably a good idea. Because it wouldn't really make sense for something to have a Japanese name in this vaguely European fantasy world. The fact that characters seem to have exclusively Germanic and Romantic names (As far as I've seen. There's at the very least no Japonic names.) seems like a good indication that they aren't actually speaking Japanese here.
Early training for being a queen. The management training.
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Tho I wonder if she organized it with supervision or not. Well, it should be. I mean, who in the mad planet leave a total newbie to the middle of warzone called politics without any guidance... That means the fight is not about the wrong faction seating, but more to personal issues...
Ok, so in chapter one she says she is 5 years old (twice no less) and in this chapter the prince is seven years old when he first meets her. So how is she four years younger than him?