Confirm her fears... and prepare her for the fun.

'Oh, yes, that's largely the gist of things,' you shrug, and watch Karen flinch in response. 'Although I could make you enjoy it, if I wished. I can make you think and believe anything I want, in fact. Part and parcel of the program I paid a large quantity of money to enlist in.'

You take a moment, then, to reach out and cup one of Karen's breasts, gently, in your hand. She's soft and warm beneath your touch, heaving with her deep and rapid breaths. Squeezing, you eventually narrow your grip until you are holding little more than her nipple, through her dress, between two of your fingers.

'And when I'm done with you, when this day is over,' your eyes slide, cool and in control, to hers. 'I get to decide how much of this you remember. I can make you forget, or just supply an interesting story to replace the time of yours I've taken... Perhaps I'll make you believe you spent today in a glory hole, sucking anonymous cock for no reason. Or that you, spur of the moment, opted to invite some homeless people into your home for a gangbang. You know, some shameful, humiliating little way to spend the day, to keep me safe.'

Karen whimpers, and you lean in closer, 'Or maybe I'll make you keep your memories of today. Maybe I'll commit as much of your brain power as I need to recalling my day with you in perfect clarity, with just one little control on your mind to prevent you from speaking about it. Maybe I'll make it so you remember me, and what we did together, whenever you have sex, whenever your pussy is filled, whenever you cum... and as a bonus, perhaps that memory will make you hornier than you've ever been before, every time. I can do that, you know.'

'I do know...' Karen's voice is tremulous and small.

'"Master," Karen. Call me Master, today...'

'I know, M-Master...' The word is dragged from the woman, a stammer the only hint of her resistance to it. But the resistance is still there, and if it exists, it's there for you to stamp out. An idea drags a smile to your lips.

'A thought does occur to me, though,' you say. 'I can actually make you forget me, though I doubt I will, personally. Keeping that in mind, isn't it possible that someone else already got to you, and that they erased the incident from your mind once they were finished fucking you? How many times have you been brainwashed and used thus far, I wonder?'

The jab clearly lands home, followed as it is by a wide-eyed stare from Karen, her mouth opening as though she wants to say something, though nothing comes out. There is, however, more to be done.

'Hell, they could even make you want it, Miss Gillan,' your voice is low and private, just for the two of you. 'Make you want it more than you've ever wanted anyone else. Karen Gillan, their good little cocksucking slut... and then you forget. It's all gone, except that it happened: you really did deep-throat them, let them fuck your ass, swallowed their cum...'

Your choice of language isn't a coincidence, the shift from speculation to concrete, literal wording designed to shift Karen's train of thought onto a true consideration of the scope of what you're saying. And now, for the coup de grace...

'... Or maybe they _don't _make you forget,' you whisper, appearing to tilt the idea around in your head yourself. 'Ever had a wild, passionate night with someone, Miss Gillan? Are you confident that your lust for them was truly your own?'

Karen hangs in her bondage, limp and shaking, your words washing over her, the specter of your control dangling over her head and making every suggestion dangerously plausible. If you let her recall this when she leaves, she'll spend the rest of her life questioning her desires, examining her relationships, fearful of any hint of lost time.

Even if you let her forget you, then, you'll have left your influence in her mind.