Nephthys, the daughter of Geb and Nut, was one of the Heliopolian Eniad, in which she was the wife and sister of Set. Her loyalty, however, seems to have been to Osiris and Isis, her brother and sister, rather than to her husband, for she helped Isis to collect the dismembered parts of Osiris which had been cast into the Nile by Set and together they embalmed his body. With Isis she mourned the death of Osiris and later she became the protectress of the dead along with Isis, Neit and Selket.

According to another myth she encouraged Osiris to drink a large quantity of wine and then seduced him, eventually giving birth to the god Anubis.

The Egyptian form of her name was Nebethoot or Nebthet and she wore the hieroglyph of her name upon her head. Like her sister Isis she is shown at times with winged arms and could take on the form of a kite.