At the same time, though as soon as you read something like "boneless blue" and if you're given the little push that she's talking about the sky... somehow the bones / clouds thing makes sense...
Agreed. Even to me as a foreign speaker, it was immediately clear what she's talking about and made absolute sense when I read the story for the first time. I know I liked that phrase instantly.
I feel the same way about the boiling mountain idea... somehow I kind of feel like I know what she means even though it doesn't make logical sense. I suppose that's what I mean about poetic aspect that I sense in her language.
I think the mountain boiling with demonic energy is a bit more far off, a bit more into the field of fantasy. But maybe that's just me, maybe I have too much of it (fantasy, that is). I can easily see the mountain boiling, bubbling and being wobbly - just like a highly piled up jelly pudding, when you shake the plate. But you have to picture it in slow motion of course.
As if the mountain were rearing up (again: in slow-mo) like a horse (or bull), to shake off the rider; the mountain was rearing up to shake off the two intruders who had lived in its paradise long enough.