Yayati is Son of Nahush who belongs to Chandra(Moon’s) dynasity. Padma purana Describes how Yayati attained Vaikunta (Vishnu Lokha).
King Yayati spreads Vaishnava-Dharma
As Said by Matali, the attainment of Vaikunta by performing Ekadasi vrat, Yayati follows vaishnav dharma to attain vaikunta. Yayati gives instructions to follow Ekadasi vrat to his entire kingdom.His kingdom soon became free from sorrows and every one was attaining Vikunta (Vishnu lokha). King Yayati enjoyed an unbelievably long life for one Lakh divine years ruling his kingdom. Indra got worried of Yayati’s kingdom increasing popularity and feared, Yayati would soon become the ruler of heaven. Indra ordered Kamadeva and Rati to find some means to make king Yayati weak. Kamadeva accompanied by other Gandharvas went to Yayati’s palace for the stage play. As the play started, Rati succeeded in corrupting the thoughts of Yayati. So finding the opportune moment ‘Vriddhavastha’ (deity of old age) and ‘Kamadeva’ entered Yayati’s body.This way the deities were successful in their plan and now the signs of old-age started to appear in Yayati.
Yayati marries Ashrubindumati
Once Yayati went for hunting and chased a Stag which led him into deep forest. Yayati being tired went to the near by lake and quenched his thirst. Later on Yayati herd sweet voice and followed that direction. He saw a woman singing a song accompanied by another beautiful woman and wanted to marry her.
The woman who is singing is Vishala daughter of Varun and her companion is Ashrubindumati daughter of Rati. Varun’s daugther told Yayati that he can marry her friend only after he shed the signs of his old age. So Yayati went to his palace and asked his two sons Taru and Yadu (Devayani is mother to these both) to exchange their ages, but both of them refused. Yayati cursed both of them. Yayati asked same question to son Puru from his other wife named Sharmishtha. Puru agreed without any hesitation. Yayati became happy with Puru and appointed him as his successor.
Now, Yayati became young once again and went to meet Ashrubindumati. But Vishala dint want her friend to stay as third wife and put a condition to Yayati that her friend should be given superior authority compared to other two wives. King Yayati agreed to the condition and married Ashrubindumati. They lived as a happy couple for twenty-thousand (20,000) devine years. Later Ashrubindumati wanted to go on pilgrimage and visit all the lokhas (Indraloka, Brahmaloka, Shivaloka and Vishnuloka). So Yayati went to Puru and thanked for his sacrifice stating that its time to exchange their ages once again. Yayati and Puru then exchanged their ages. Yayathi handed over his kingdom to Puru and visited all the divine places. Yayati ultimately attained to Vishnuloka.