Lamastu/Lamaste/Lilitu/Lilith/Lamia is not Jewish .This is a Sumerian myth that was passed to the Akkadians , the Assyrians , the Jews and the Greeks . I think Wikipedia article is pretty clear .

In the myth this demon is half a woman and half a serpent and this is why Christian bibles up to 17th century had this image depicting the demon in the garden of Eden .

Why i am writing this ? because most of Semitic lore ( yes including Christianity , Judaism and Islam ) comes from the Sumerians .

Also yes Lilitu is a feminist figure because in the myth she was created as an equal to Adam and left the garden on her own volition after an argument with Adonai .