User blog comment:Omega natsu2/Fairy Tail Episode 212: Juvia vs. Aries: Clash in the Desert!, Review./@comment-24039250-20141215200139

Mega, to answer your question on why Ophiuchus is a woman I have to throw out there what she is likely modeled as. Have you ever watched/read Soul Eater? If not, there is a character that has an affiliation with snakes and at one point is a nurse in the anime/manga. Her name is Medusa and if you look at the design of Ophiuchus and her, you will see that they look similar to each other. I'm assuming that this is a Fairy Tail version of her, much like how we got Fairy Tail "Yu-Gi-Oh".