Pixies are the forest fae that condense where Faesong, Melera's emotion-current, pools thickest in the living world. They do not control or command emotion, the way an old bestiary line once held. They are emotion — gathered out of one patch of the world until it wears a small winged body — and they resonate with the feeling of everything around them rather than bending it. They hear Faesong because they are made of it.
The full account belongs to the Pixie race entry: the courts ranked by resonance, the condensation that makes a new pixie, and the five heritages. They should not be confused with the Faeries of Faesummer, which are creatures of Aurus that hear the song without being made of it.