She is Baalhu, one of the Ancients. Legends say she dwells in the mountains, waiting for the brave and desperate to seek her out. She richly rewards those who find her, granting them anything they desire… and taking their souls as payment. Before they die, those mortals are forced to return to her. She places their souls into the bodies of bluebirds, cuts out the heart - - staining their chests red - - and sets them free into the world to be her eyes and ears.
Never tell a secret when there is a bluebird nearby. She might hear you.