Beneath a hexagon of lamps suspended over a twilight blue carpet stood a tilted bench of black vinyl. Close to it arose a rack, bearing console and computer monitor. Unlike Erica and Cheryl, who sat either side, the figure upon the bench was quite immobile, her upper body enclosed in gleaming black leather and crossed by straps. Had it not been for the short length of tubing and rubber bulb that hung from where the mouth should be, her head would have mimicked an unfinished sculpture in polished obsidian. Her lower body was naked and because her ankles were fastened beneath the bench, her thighs were held wide apart by its width.

Images floated in Carmen's darkened world; a magic lantern in a black vault. There was the small room to which they had earlier taken her. Then she had at least been able to see, though the straitjacket had restrained her limbs and the rubber ball had prevented speech. There was the combined bidet and lavatory bowl. There, hanging from its chrome stand was the pink rubber bottle. There the clear flexible pipe coiling down to end in a long plastic nozzle.

They had fastened her over the bowl where she could see herself in the large mirror, then Erica had looked on whilst Cheryl's latex-gloved hand inserted the nozzle cool and hard up her rear passage before turning the small valve. Could she deny the sensuality that vied with her shame as tiny bubbles shivered through the coiled plastic pipe? She had felt the urgent churning within as Cheryl withdrew the spout. She had realised she was about to lose control of her bodily functions in front of them. Could any humiliation have been greater?

But in spite of what had happened, when Cheryl had soaped and washed her intimately, she had experienced other sensations. Erica had noticed and called out, 'Careful, don't let her come!'

Before releasing her from the bowl they had fitted the rubber hood that denied her sight then inflated the bladder that slipped and squeezed inside her mouth. Why had they not hooded her before? Then her thoughts were distracted by voices outside.

'I think it's important,' said Erica as the monitor glowed with life, 'that we record the most effective frequencies for future reference.'

Cheryl leaned forward, deftly inserting one rubber-sheathed steel probe into the girl's pussy then easing the other into her anus until its hard, cool form pushed with lubricated firmness into her rectum. Through nasal perforations in the helmet emerged a low moan.

'She's an ideal subject,' remarked Cheryl. 'I've seldom encountered anyone who climaxed so readily under controlled conditions but wouldn't it be easier to have her strapped into the chair?'

'I'm convinced this little slut will climax under any conditions,' remarked Erica, adjusting dials on the console, 'but if we had her in the chair she'd be able to twist about and might upset the readings. On here she can't move at all.' Her fingers touched a small green button. 'Right, I think we'll start on the lower frequencies first. One probe at a time, then both together.'

A dull humming began and both watched the oscilloscope intently as it pulsed and began to amplify. Soon, their concentration was broken. Both looked around at the figure on the bench. From beneath the helmet came a stifled moan. Erica glanced back at the screen, saw the pulses speed up and increase almost to the limits of the scale. 'Good God - already!'