Omecihuatl is the Aztec goddess of creation and wife of Ometecuhtli. She lived in the highest heaven Omeyocan with Ometecuhtli. Her name means "Lady of Duality".
Originally there was no light, but Omecihuatl and Ometecuhtli could sometimes see the light of the eyes of the monsters. Omecihuatl one day touched a monster and it turned into a star, from then forth she and Ometecuhtli touched whatever monster they could find. This filled the sky with stars and the heavens with light. After this, the two decided to have children. They had four sons, Quetzalcoatl, Xipetotec, Tezcatlipoca and Huitzilopochtli, whom created the earth with one of the remaining monsters. Omecihuatl and Ometecuhtli were happy with the work of their sons and sent drops of light to earth to be the souls of children.