According to Indian mythology who was Madhavi?An eternal virgin?

The story of Madhavi the daughter of Yayati?

An eternal virgin?

King Yayati's daughter, Madhavi, had the power to destroy her virginity every time she had a child.? 

One of the most amazing stories of the Mahabharata is the story of Madhavi. Yet very little is known about him. Madhavi was the daughter of Yayati and an apsara. Madhavi had divine powers to remain a virgin forever. He had the boon of giving birth to four brave and strong sons who were fit to rule the world. Galav, a disciple of Vishwamitra, remained adamant on giving Guru-Dakshina. Vishwamitra demanded 400 Divyalakshmi horses to teach him a lesson. In consultation with many people, Galav eventually reaches King Yayati of a very powerful lunar dynasty.

Yayati was unable to give such horses, but to make up for this, he presents to Madhavi, his daughter Galav, and Yayati tells him about Madhavi's divine powers. Galav then takes Madhavi to the king of Ayodhya, Hariyava, and gives birth to Madhavi Vasumanasa in exchange for 200 horses. After this Madhavi regains her virginity. Galav then takes her to the king of Kashi, Divodas, and Madhavi gives birth to a son Pratardhana, regains her virginity and leaves the son with her father like the previous son. Galav takes 200 horses from Divodas. Next Galav takes her to the King of Bhoja, Ushinara and Madhavi gives birth to a son named Sibi in exchange for 200 horses. Therefore, now Galavas would have 400 Divyalakshmi horses and there is no king on earth who has such horses.

With 600 horses, Galav returns to his mentor, Vishwamitra. Because Galav had less 200 horses, Vishwamitra offered Madhavi to have 200 sons instead of one son. Madhavi gives birth to a son, Ashtak, who later became a great king. After giving the Guru-Dakshina, Galav went to the forest.

Vishwamitra sends Madhavi back to her father Yayati. She was still a virgin due to her divine power. Yayati arranges Madhavi's marriage but, completely indifferent to the marital life and progeny, Madhavi refuses to marry again. She goes to the forest and lives there as a monk.