Oceanids
Greek and Roman sea-nymphs that numbered three thousand.
The Titan Oceanus, son of Uranus and Gaia, fathered all the sea gods and nymphs except Poseidon. His wife Tethys was the mother of Styx and all the rivers of the Underworld.
Nymphs were female spirits of nature with long lives, not immortals or deities. Each of the three thousand, playful spirits typically fell in love with mortal men and presided over a certain form or body of water. Zeus and other gods pursued them, and Zeus eventually won over Metis who became his wife. Gaia gave Metis a prophecy, saying after she gave birth to her daughter, she would have a son that would take over Zeus' position on Mount Olympus. Zeus was frightened and swallowed his expectant wife, who then lived inside him. Hephaestus was born, and split open his father's skull with an axe, and Athena came out in full armor. Another nymph, Tyche, was famous for determining people's individual fortunes. She loved creating dramatic or unknown outcomes, and would suddenly change her oblivious victims' fates for entertainment.