I’ll go ahead and move the discussion that’s getting further and further away from this week’s reading here.
Anyway, spoilers
Ah, now we are at my favourite part – speculation about how the magic works. [book 3 spoilers] In the temple scene, Ferdinand says events like these are very common in children with mana who lose control of their emotions (letting mana loose in their bodies) and that the effect depends on the amount of mana, with crushing being on the high end. And even though he’s from noble society where having lots of mana is the norm, he would also have to have had lots of experience with noble children who were lacking of mana and were sent to the temple as a result. Also, shumils change the colour of their eyes and I don’t think they are shown to have a lot of mana.
Well… small children make up nonsensical words all the time. As for the weirdness, I would bet it’s more like an uncanny valley type of thing, since she unconsciously behaves in ways that are subtly off. Though I’m sure a lot of it is offset by most people naturally not really paying a lot of attention to children, especially other people’s children. Benno and Otto are kind of an outlier here, since observation is everything in their profession.