Kalpavruksha is a samskrit word for the tree which grants one's wishes. Same way, once Parvati found this Kalpavruksha and wished she must get a girl child who looks exactly like her. Her wish is granted. The girl thus born is Ashoka Sundari.
Parvati granted a boon to her that daughter will marry King Nahusha in future. Nahusha is a handsome prince. Parvati thought he is the ideal match for her beautiful daughter. But as the time passed by, Ashoka Sundari grew up to become a beautiful lady.
At that time, a demon named Hunda tried to marry her forcibly seeing her beauty. That time, King Nahusha came to Ashoka Sundari's rescue and defeated the demon in a fierce battle. Nahusha came to know that Ashoka Sundari is looking for him. He told his identity and married her.