A Shameful Punishment by Emily Tilton

Katrina Cole swore loyalty to the Pretorian Guard. Then she betrayed them. Now she has been caught, and her punishment will be more shameful than anything she could have ever imagined.
She will be bound, naked and helpless, as she is thoroughly and painfully strapped. Then she will be used in the most humiliating ways possible, taken over and over again first by the man who trained her and then by one guardsman after another. Her begging and pleading will be ignored as one savage climax after another is wrung from her quivering body, and by the time her ordeal is complete she will be left in no doubt that she has truly been utterly and completely mastered.