I like the flow, the progression and the images. I very much enjoyed reading this.
I run into a problem with "her" in this context:
> It keeps her so safe and sound
Who is "her"? One would assume it to be "secrets", but apparently it is not. Maybe if you started out with:
"Her silence keeps all her secrets"
Then it would be clear that "her" is neither the silence nor the secrets: they both belong to "her". Next, "If nothing could reach her" is a bit abstract. I might relate it back to the previous lines, perhaps something like this:
"If no secrets were revealed, No harm could ever befall her."
> She is hiding her real entity silently
This use of "entity" is unusual. It's not incorrect, though. Still, I might consider this; it's more easily understood:
"She is hiding her real identity silently"
> "What a storm is hidden"
The article is a problem. This is a very difficult problem for anyone (_everyone_, in my opinion) who is not a native English speaker. Try this (the "a" is removed):
"What storm is hidden Under this mask of hers"
I am profoundly impressed that you can write like this in your second language. Bravo! bent