Tied as she is to the stake, it is just a matter of time before she becomes very uncomfortable. They won’t have to sex her to make her squirm! And the way she is fastened, the only freedom of movement she has will be in her hips and thighs, swaying and beckoning to any and all prospective buyers. Since she’s gagged she cannot protest that she is of noble birth, nor explain to the crowd that she does not mean to be so wanton with her motion.