In search of lesser-known tales, I recently read a few of the Color Fairy books that Andrew Lang edited in the early 1900s. I was expecting something rather pared-down and sanitized, but found that Lang actually worked hard to avoid this stereotype. Many of the stories feature characters that are more rounded (and chatty) than usually appear in such collections.
This painting is based off a character from The Castle of Kerglas, from Emile Souvestre's Le Foyer Breton, which was collected into the Lilac Fairy Book. The story follows a dim young man called Peronnik on his quest to steal some objects from the magician of Kerglas. Just before he reaches the castle, he encounters a mysterious woman in a black satin dress. Peronnik thinks she's Moorish; later she tells him that she can kill the magician for Peronnik with a touch of her finger because, she says simply, she is the plague.
Below is an inverted version of the painting. I usually try to avoid Photoshop tricks, but in this case I thought the otherworldly look was in keeping with the woman's supernatural abilities.