Nereus was a marine deity in Ancient Greece and a gentle, old man who was just and would tell nothing but the truth. He was the eldest son of Pontus and the Mother Earth Gaea.

Nereus had the tail of a fish and the torso of a man. He was bearded and had hair as white as the foams of the sea. Nereus' home was at the bottom of the Aegean sea, in a splendid palace built inside a cave.

Nereus married Doris, a fine-haired daughter of Oceanus, the titan of the seas. The couple was blessed with 50 beautiful mermaids, the Nereids, who with their sweet, enchanting sound protected the sailors.