Bob reached for the controller, flicked a switch and an electrical hum emanated from deep in the machine's bowels.

He turned the speed control, the hum intensified and the massive flywheel started to turn. Of course this had the effect of sliding the piston away from under Magda's feet, causing her to suddenly drop down the chute by the eight inch height of the piston.

"Urgh," she moaned piteously.

The piston was moving very slowly and it look a few seconds to reach the other side of the box. Then it started to return. Despite her earlier insistence, Kasia found that she could not keep her eyes away from the fate that awaited her mother.

"No no no! Stop!" She yelled as suddenly she realized what was about to happen. She suddenly squirmed under Bob helplessly trying to escape, then her protestations dissolved to a whimper as he slammed her head down and rammed home his cock.

Emma was savouring the moment, and started thrusting her blade deeper into Maisie's cunt, which caused the most intense bubbling shrieks of pain and anguish. A patch of red appeared as her crotch.

Then the piston reached Magda's chubby feet and painted toenails, and pushed them inexorably towards the grill. The sudden change in her footing caused the mother to twist a little and slump over to the near side. Her mangled left breast spread out against the glass, causing the wounds to open, revealing yellow fat, and leaving a bloody smear.

Suddenly, Magda visibly stiffened in pain as her feet reached the end of their journey, twisting around sideways at an unnatural angle. Then as they reached the grill, with a deep, solid sounding crunch, they were grotesquely flattened before being forced through the inch-square holes in a grisly burst of gore.

Droplets of blood sprayed out and with a plop, the mangled meat and bone dropped into the tray in a little pile, comically adorned with green spangles.

As the piston once again retreated, with a satisfied 'shick' sound, Emma slowly withdrew the blade from Maisie, slick with blood. Maisie's screams had subdued a little, becoming a sporadic wailing.

Bob turned up the speed a notch and started to fuck Kasia fast and hard. Kasia was panting and groaning in distress. But occasionally she would be swept with a wave of pleasure, making her feel guilty. As endorphins flooded her system, the pain lessened and she darkly wondered if she was actually starting to enjoy it.

Magda fell another eight inches. Now her curvy calves were in the line of fire, and the piston was returning again, the little extra speed seemingly imparting it with more purpose. Emma once again plunged the blade deep into the little one and giggled at her shrieks.

As Magda bled out, the pain receded into the far distance. She could see her daughters being brutally raped through the Plexiglass. There was no-one to blame but herself, she thought. She wanted to say sorry to them but now it was too late. She had no strength left to speak.