According to Encyclopedia Britannica, Apsara, in Indian religion and mythology, one of the celestial singers and dancers who, together with the gandharvas, or celestial musicians, inhabit the heaven of the god Indra, the lord of the heavens. According to Wikipedia, in Hinduism, the Gandharvas are male nature spirits, husbands of the Apsaras. Some are part animal, usually a bird or horse. They have superb musical skills. They guard the Soma and make beautiful music for the gods in their palaces. Gandharvas are frequently depicted as singers in the court of the gods. Gandharvas act as messengers between the gods and humans. In Hindu law, a gandharva marriage is one contracted by mutual consent and without formal rituals.