Obeaune

Obeaune is a creature with the head and upper body of a woman and the tail of a fish. She seems to have a bad hair day, her tangled and uncombed hair harms other creatures with the slightest damage. Besides, she isn't nice to let eyesores get near her. A female mermaid that attacks with its wild, flowing hair. Whether or not its male version is Merman is still under debate.

Ragnarok Online II
In RO2, there are 3 variations of this monster:
 * Obeaune
 * Coral Obeaune
 * Wandering Obeaune