Tetchi arü Ngu'i is named in the origin narrative as the wife of the hero Yoi and the immediate cause of the fishing that peopled the world. It was she who cast the mixture of blood, flesh and seeds into the reddened waters of the Eware creek, where it turned into fish; grieving that she had thrown it away, she asked her husband to draw it back out, and so Yoi took up his baited line and fished the ancestral Tikuna, the Magüta, from the river. Her act supplies the material of humankind while Yoi supplies its ordering, and the two together frame the central Tikuna myth of origins.