A Liar's Crystal
When Faustina was at the cabin, she and Eula encountered all kinds of people from the small town below—both kind and unkind, trustworthy and dishonest, good and bad; these people took the form of either the elderly who were senile and (sometimes) very patient, to adult men and women looking at their doings with discontent whilst they receive treatment and medicines.
But people from Nebel—the town below—were poor enough to rely on mountain witches for medicine, so they pretty much had no room to complain. Nonetheless, people are still people. Even if their mouths cannot say their discontent directly, it showed into their face. Eula said so herself that their distaste was even as clear as the river water in the forest.