Slave Cynthia: My Mistress, the Artist (Abusing Cynthia)

Cynthia was thrilled to learn that her mistress was having a dinner party, and secretly hoped that she would be used and abused in front of all her mistress's friends. What her artistic mistress actually did to Cynthia, however, came as a painful and humiliating surprise that thrilled her to the bone.
The third short story in the Abusing Cynthia collection.