The princess who married a sage
Sukanya, a princess, curiously pokes at two bright sparks in an anthill. She is horrified when she realises that the sparks are actually the eyes of the great Sage Chyavana. He is blinded and a blight descends upon the entire kingdom. There is respite only when Sukanya agrees to leave her family and her royal home to marry the sage and serve him faithfully.
This version is taken from the Mahabharata, but references to Sukanya's integrity appear in the Bhagawat Purana, the Devi Purana and the Rigveda. She remains faithful to Chyavana, eventually shaming even the heavenly twins, the Ashwini Kumaras.