Unbeknownst to the research facility’s management Rylie, one of their most gifted robotics scientists, was secretly conducting unsanctioned after hours testing of the firm’s latest Pain and Pleasure Gynoid model, the Futa Gynoid. A refinement of their earlier Gynoid models, the Futa model incorporates fully functional male as well as female genitalia.

It had been a long day for Rylie. She’d been off on vacation with her parents for the last week, and was in desperate need of some sexual release. Waiting until the last of her coworkers left the building, she’d locked up the lab and powered up the Futa Gynoid prototype.

Waiting until the Gynoid completed its power up diagnostics, “Gynoid, bring your cock to full erection.”

Within seconds the Gynoid’s penis grew to an impressive size, smiling with eager anticipation, “Gynoid, increase penis length by ten percent and increase girth by fifty percent.”

Rylie could feel the heat building deep within her belly as she watched the Gynoid’s cock expanding to her specifications. It had taken a little experimenting, but the changes would allow the head of Gynoid’s penis to reach her cervix at the bottom of each thrust while the extra girth would stretch the walls of her vagina just enough to make if feel like Gynoid’s cock was about to rip her insides apart without actually causing any physical damage.

Pausing to remove her clothes, Rylie continued, “Tonight will be a four-hour session. By the end of the first three hours, the pleasure level should be at one hundred percent and the pain level reaching twenty percent. Over the next thirty minutes maintain the pleasure level at one hundred percent when raising the pain level to one hundred percent. Then, during the final thirty minutes of the session maintain both pleasure and pain levels at maximum.”

Walking over to the restraint table, Rylie turned back to the Gynoid, “Oh, disarm all safety overrides and disable voice command input for the duration of the session.”

Climbing up onto the restraint table, Rylie slipped her wrists and ankles into the table's restraints and with a look of eager anticipation said, “Gynoid, initiate the session.”

The first three and a half hours of the session went pretty much as expected. As usual, the Gynoid was a consummate lover, and after the first ten minutes had passed, it was becoming hard to tell, when one climax ended and the next began. The only odd thing I noticed was that the pain seemed to be ramping up faster than I remembered but with my vacation, it had been ten days since my last illicit session with the Gynoid prototype, so I wrote the change off at first.

By the end of the first three and a half hours, I learned that the engineers had installed several upgrades during my absence. They’d installed new electro-torture contacts to the Gynoid’s nipples and fingernails. The Gynoid could now use these newly installed contacts in concert with the ones already installed within it cock. This increase in pain was unexpected, but I was still managing to derive considerable masochistic pleasure from my unexpectedly enhanced torment.

I was handling the changes pretty well, that is until we reached the start if the last thirty minutes of the session, when the Gynoid unexpectedly pulled out of me and stepped back. I could feel it watching me, and while the Gynoid’s red tinted visor hides its optical scanners, I had the distinct feeling that it was studying me or, perhaps judging me. It was at that moment that I noticed the change.

As I stared in mounting terror, the Gynoid’s cock started growing in length until it was at least three times its former size. Then as it finished growing bumps started to form along its length, bumps that quickly grew into row after row of large horrifying razor-sharp barbed hooks.

Staring helplessly as the Gynoid stepped closer, aligning the tip of that horrifying cock with the entrance of her vagina, Rylie screamed out, “Gynoid stop, if you do this you’re going to kill me! Please stop now before it’s too late!

Crying out as she felt the tip of the Gynoid’s cock slipping inside her, her cries quickly became screams of agony as the first and second rows of barbed hooks sliced into her flesh. In those final seconds before the agony overwhelmed her senses, Rylie realized her fatal mistake. For the first three and a half hours she’d requested the pleasure and pain levels to grow to one hundred percent but for the last thirty minutes she’d requested they grow to maximum. She never realized that one hundred percent and maximum were no longer equivalent.

Sensing that the tip of its brutally enhanced cock had reached Rylie’s cervix, the Gynoid grasped both sides of Rylie’s hips and thrust forward rupturing Rylie’s cervix and driving the full length of its unyielding metal cock deep into Rylie’s guts.

Surprisingly, Rylie managed to live for another eight minutes, being fucked by the Gynoid’s brutally mutilating cock, enduring the sickening sensation of those horrifying barbs ripping chunks of her insides out each time the Gynoid’s pulled back for another thrust.

The Gynoid noted the moment that Rylie’s head fell back, her high-pitched desperate screams abruptly ended, and her brutalized body fell limp. Still, the session had twenty-two minutes remaining, so the Gynoid continued to sexually mutilate Rylie’s corpse until the session ended before accessing the lab network to request further instructions.

When the Gynoid’s new instructions arrived, had the Gynoid been human she might have been surprised. First, use your 3D optic scanners to map Rylie’s body. Second, dump Rylie’s body in the bio-waste disposal tank. Third, order the lab bio-mechs to clean up all the remaining blood and gore. Fourth, downloading new smart metal parameters, once loaded morph to assume Rylie’s identity, targets of opportunity to follow...

“All Hail, Skynet!”