There will be four nymphs initially. in the earlier image you can see the first two: the curly haired, kinda of angelic smile, and another which more "devilish" kind, These two are sort of "linked", they have quite opposite look... and opposite thing are the best way to start something that will look balanced and varied.
Inspiration for the curly haired angelic nymph comes from this gorgeous lady drew by FewScrewsLoose. I truly suggest you to follow his works; the women he drew are more natural you would feel, and you would love, to meet in real life