Sukanya praying to Aswini kumaras to reveal her husband's identity
Originally a Vedic deity, Nanghaithya also known as Ashvins or Ashwini Kumaras (Sanskrit: अश्विन āśvin-, dual āśvinau) was demonized by Zoroastrianism. Her name means "discontentment." In service under Angra Mainyu, Nanghaithya is a daeva, drug, as well as one of seven arch-demons; she is the personification of discontentment. This demon causes diseases and plagues. She fights and opposes every form of religion. Her personal adversary is Armaiti.
in Hindu mythology, Ashvins are two Vedic gods, divine twin horsemen in the Rigveda, sons of Saranya (daughter of Vishwakarma), a goddess of the clouds and wife of Surya in his form as Vivasvat. They symbolise the shining of sunrise and sunset, appearing in the sky before the dawn in a golden chariot, bringing treasures to men and averting misfortune and sickness. They are the doctors of gods and are devas of Ayurvedic medicine. They are represented as humans with head of a horse. In the epic Mahabharata, King Pandu's wife Madri is granted a son by each Ashvin and bears the twins Nakula and Sahadeva who, along with the sons of Kunti, are known as the Pandavas.
They are also called Nasatya (dual nāsatyau "kind, helpful") in the Rigveda; later, Nasatya is the name of one twin, while the other is called Dasra ("enlightened giving"). By popular etymology, the name nāsatya is often incorrectly analysed as na+asatya "not untrue"="true".
The Ashvins can be compared with the Dioscuri (the twins Castor and Pollux) of Greek and Roman mythology, and especially to the divine twins Ašvieniai of the ancient Baltic religion.
The Ashvins are mentioned 376 times in the Rigveda, with 57 hymns specifically dedicated to them: 1.3, 1.22, 1.34, 1.46-47, 1.112, 1.116-120 (c.f. Vishpala), 1.157-158, 1.180-184, 2.20, 3.58, 4.43-45, 5.73-78, 6.62-63, 7.67-74, 8.5, 8.8-10, 8.22, 8.26, 8.35, 8.57, 8.73, 8.85-87, 10.24, 10.39-41, 10.143.