The Duchess had no words to explain what she had just experienced and even as she said it, she knew the word 'incredible' had not been enough to express her satisfaction.
What had she felt?
Well, she had felt a myriad of emotions that all seemed to lack a cause or any form of external stimuli and yet simultaneously had it all in spades.
What she had felt was a simulation of what perfect arousal and climax would feel like to her... Except for the torture of course.
Hal had mostly bypassed all of her physical sensory nerves and focused on her mind... Specifically, the section of her mind in charge of arousal and pleasure.
What she had felt was all mental and not really physical but considering how real it had felt to the Duchess, then its' reality could not be debated.