Hemera was the primordial goddess of the day. She was the daughter of Erebus and Nyx.
Hemera was the daughter of Erebus and Nyx, the primordial darkness and night. She was the female counterpart of her brother and consort, Aether (Light). Hemera left Tartarus just as Nyx entered it; when Hemera returned, Nyx left:
"Nyx and Hemera draw near and greet one another as they pass the great threshold of bronze: and while the one is about to go down into the house, the other comes out at the door."