Gorgons

After the defeat of Uranus, Gaia mated her second son, Ocean. Their children are the gods of the sea, rivers, lakes and generally liquid asset.

Children of Pontus and Gaia were Nereus, the Thavmaton,  Phorcys and Kito. Phorcys and Kito (brothers) "mingled" and gave birth to three Graiae, also Scylla and Charybdis, and the three Greek mythology Gorgons (Vigour, Euryale and Medusa).

It is said they were Kentafrisses, which turned into hateful monsters by Athena because of Medusa. Often associated with the Sirens.