According to the Fortune Teller, the Hairfish is a cursed, monstrous fish whose curse was cast long ago by an unknown sea witch and only a school of silver fish will turn a Howling Hairfish back into a normal fish. The only Howling Hairfish that is able to speak is Flounder.
As a cursed Hairfish, he is a gigantic lycanthropic fish with a purple scaly body, dark purple stripes on top, blue border lines on his fins, thick black bushy eyebrows, blue bags in his eyes, whiskers on his head and chin, a black dog-like nose, big yellow eyes and enormous and deadly sharp teeth.
Role in the series
A regular Hairfish appeared where Sebastian will never be forgiven by Urchin once it ate the trophy. Urchin got mad at him that he would never forgive it. Later when the gang arrived at the Fortune Teller's place to find out how to break the curse, the orb she showed them features a school of silver fish turning it into normal.
Another variant of the species was a blood-red colored variant and is actually Flounder who was cursed after feeling a "little hairy". He started to attack the village and the villagers formed an angry mob to capture him for the destruction. Flounder started to repel himself from the great white sharks; after that, he reverted back into his normal self and the mob captured him, putting Flounder in a cage inside a sunken ship.
In the cage, Flounder turned into a Howling Hairfish again and went on a rampage. Ariel used a school of silver fish to enter the sunken ship as the mob tumbled down the ship, as the silver fish turned the Howling Hairfish back into Flounder, as the villagers cheered, breaking the curse. As a result, Flounder no longer transformed back into the monster he frequently transformed into, thanks to the silver fish that helped break the curse.