"like a mermaid"
'A Mermaid' by Waterhouse
Public Domain'A Mermaid' - Credit: John William Waterhouse (1849-1917)

A mermaid is a mythological, female marine creature, possessing the head and torso of a woman and the tail of a fish.

In folklore and literature, mermaids sometimes have a malign influence on human beings; sometimes, a benign influence.