Also known as: ネレゲイド
One triplet among the Demons of the Rift in Final Fantasy V. Its partners Phobos (FF5) and Triton (FF5) were designed to be the game's Magus Sisters equivalent.
It, along with its siblings, are named after moons. In Nereid's case it is a moon of Neptune (Planet), although the Japanese name added a ゲ (ge) to make it Neregeid (ネレゲイド), likely to evoke the word Renegade (レネゲイド).