The snake twisted faster, coiling in and out of both girls.  "I'm sure you can, my Nyla," Siona purred.  She pressed their bodies together, taking the serpent deep inside and pressing it ever deeper into her lover, 'til their labia's pressed together over the writing serpent.  With a needy coo, the ebony girl bucked her hips against her lover, rubbing thier petals together while the serpent coiled and vibrated within.