L'Origine du monde(I) -Portrait de Jo, la Belle Irlandaise.

Painting by Gustave Courbet
Maybe the model of the L'Origine du monde by Courbet.
Joanna Hiffernan had a six-year relationship with American painter James Abbott McNeill Whistler, inspiring some of his most important works like Symphony in White, No. I: The White Girl and Portrait de Jo, la Belle Irlandaise. However, Whitsler's family didn't like Hiffernan, and his parents had to find alternative accommodations when visiting their son in order to be away from her. In 1866, Whistler left for Valparaiso (Chile) for six months, during which he had an affair. Shortly after returning, the couple split. She was the favourite model of Courbet.