"One" Jenn said as she heard the belt make contact with Emrys' ass. Any normal person would have at least winced but Jenn was used to far worse, sure 15 sounded a little much considering it was over a broken string but it wasn't more than all his transgressions combined.
She had noted her Masters technique and knew from experience that it would hurt like a bitch but would not cause any permanent damage. Jenn was content with the punishment as she understood it and that her Master would do the same to her should she step out of line unwittingly. She wouldn't do so on purpose.