Language
What's a language?
It's words and sounds. It's signs and meaning. How could that be dangerous?
Robin didn't understand the panic of the other scholars after they learned that she had taught herself a language.
She may have learned the signs, words, and sounds of that ancient language but never the true meaning of it.
It took her many years to master the language's meaning truly.
And as Robin finally understood its meaning, she also understood the panic of her fellow deceased scholars.
Because a language hid the secrets of the world.
And only Robin could reveal them now.