Well, they're not in the latest Shantae at least.
Terraria Community Forums
ppowersteef
Golden Heretic Snakeboat
It's Something.jpeg
The kamen rider
@ppowersteef They are, they replace the mermaids after you defeat the mermaid queen.
ppowersteef
oh, right...I thought there was only that one shopkeeper.
neoselket
Because in the original greek myth, lamia was a vampiric monster that ate children.