The idea of Skyping a chastity slave is perfect. He would never be safe from being teased and denied, even while she's away (or just on a date).
I like that she doesn't even give any kind of fuck that the evidence of her 'playing up' is as obvious as it can be. She knows she's got his balls in a vice - literally.
Her attitude is perfect. She's obviously having sex but doesn't quite come out and say it, despite the unmistakable evidence. Calling her experience 'one-on-one instruction' is so wicked.