Devotees at Tirupati Balaji have their head tonsuring as an offer. It’s believed that a small portion of Lord Balaji’s scalp became bald when he was hit by a shepherd. Then, Neela Devi, a Gandharva princess, cut a portion of her hair and implanted it on the scalp of Balaji. Balaji noticed it, and promised her, on her sacrifice, that all the hairs rendered by his devotes will be offered to the Devi. So, it’s believed that the Neela Devi is the recipient of the hair offered by the devotees.