All nine were painted by Margaret Brundage, who was the most popular of Weird Tales’ cover artists. She was known for her images depicting bondage and flagellation of women. Authors would insert unnecessary scenes depicting nude women being tortured or whipped to ensure their story got the cover of an issue.
The safe-word is FLÜGGÅƎNK∂€ČHIŒβØL∫ÊN
Also, What Women Want Out of Sex and Jungle Duel of Death
A much more popular topic than the Dominatrixes.
Less popular than the Slave Girls, apparently.