Marathon Mode!

"Well, can't go wrong with the classics! Pound-O-Matic, initiate Marathon Mode!"

The machine quickly replies "You have selected Marathon Mode! The sexual extremity will penetrate the subject repeatedly, building up speed as time goes on. After maximum speed has been reached and the subject has experienced orgasm, the sexual extremity will be removed. Beginning penetration now!"

Instantly, the metal rod starts sliding forward, moving the big purple dildo ever closer to your asshole. You can do nothing but watch, as the toy comes closer and closer to penetrating you. As the tip of the cock makes contact with your ass, it slows down just a bit, but still puts a fair amount of **** on your sphincter. You suddenly flinch and gasp as the 3-inch thick shaft finally penetrates your asshole.

The machine says "Penetration successful, beginning thrusting!"

With no remorse, the dildo starts sliding in and out of your ass, shoving all its 9 inches down your rectum with each thrust. You try to resist, but all you can do is struggle in your bonds and accept the pain of the giant shaft pounding your ass. It starts off rather slow, giving you some time to adjust. You gasp as the girthy rod presses against your prostate with every entry, making your cock slowly grow in size.

After a few minutes of being fucked by the machine, it says "Speed at the starting level. Raising speed now..."

Then, you feel the machine's thrusting get slightly faster. The rubber cock pounds your rectum faster and faster, rubbing against your prostate and making you tingle in pleasure, meanwhile still feeling the pressure in your body from the size of the dick. The mix of emotions has you confused, but wanting more. The machine keeps getting faster, thrusting the purple shaft in and out of you and making you moan out loud. You shoot a quick glance at Myra, but she seems to be paying very little attention to you. You go back to looking at the machine that's pounding your guts with its thick dick and just try to enjoy yourself.

After about 10 minutes of ass pounding, the machine has tripled its starting speed, leaving your ass a bright red from all the pounding. You've already gotten used to the discomfort and use it to fuel your arousal in that twisted mind of yours. The purple dong is flying inside your ass four times a second, but the machine just keeps slowly getting even faster and faster. Suddenly, all the stimulation to your prostate is too much for you to handle. Your cock is at full mast and is leaking precum, ready to burst. With a loud grunt, you thrust your hips slightly forward and spray a load of jizz in front of you, coating the machine and the floor behind it in your spunk. The machine doesn't slow down for a second in its relentless fucking spree.

Instead, it says something "Subject orgasm recognized. Speed has not reached maximum levels yet, so pounding must continue!"

You gulp from the slight fear of how fast this thing is planning on getting, but you keep your cool and try to compose yourself. Your cock is still sensitive from your orgasm, so the continuous pounding makes you moan even louder than before.

After another 10 minutes of fucking, your cock is fully erect once more and the machine shows an even greater demonstration of speed, as it thrusts your ass with twice the speed it had a while ago. You're back to moaning loudly and frequently, as your ass gets blasted by the rubber cock over 8 times a second. This gives your prostate a real workout, as it keeps getting pummeled by the purple invader, making you feel the edge of orgasm once more. You cringe and squint your eyes before letting out a hefty scream of pleasure. Your cock erupts with another cumshot, just as big as the first one. The machine is even more so covered with your seed now and so is the floor. You let out some heavy breaths after your orgasm, but realize that the machine is still going, getting even faster.

It repeats what it said before "Subject orgasm recognized. Speed has not reached maximum levels yet, so pounding must continue!"

Your cock is extremely sensitive at this point, which makes sense since you just came a second time in the span of about 10 minutes. Yet, the show goes on.

Around 20 more minutes of hardcore pumping continue until the speed of the machine's thrusting reaches unbelievable levels. It feels like an actual jackhammer has been stuck up your ass and is going at full speed. Your pleasureful moans have turned into a garbled mess of sound, as your whole body shakes from the speed of the dildo penetrating you over and over again. Wonderfully enough, your cock manages to get hard for the third time after the sheer amount of prostate stimulation.

The machine suddenly starts talking again, saying "Speed reaching maximum levels. Waiting for the orgasm of the subject..."

Suddenly, the machine cranks up its fucking speed from "unbelievably fast" to "minigun in your ass fast". The rubber dildo reeks havoc upon your once delicate asshole, now turning it into its personal punching bag as it slides in and out with expert precision and godlike speed. It basically looks like a purple blur is moving up and down your anus, or that just might be your brain shutting off from the anal punishment you're getting. Nevertheless, the speed at which the rubber cock fucks you is extremely pleasurable to your prostate, making you scream out in pleasure as your dick lets out another, final orgasm. The cumshot is surprisingly even bigger than the previous two, and lathers the machine in your jizz. You blast about a dozen good loads of semen out of your quivering cock and finally slump down in your restraints.

The machine says "Subject orgasm recognized and maximum speed reached. Terminating processes..."

The machine pulls out the giant rubber cock out of your ass. Your asshole somewhat clings to the shaft, not wanting to let it go, but it slips out anyway. The dildo retracts back to its former position while your body quivers from the sudden lack of punishment. You turn your head as you hear Myra clapping while still sitting on her table.

She says "Good job! Not everyone can withstand the marathon, but you showed great results! To be honest, you broke the record for most orgasms during the marathon! Well, except for me of course, no one's been able to break that yet! Anyway, so far, you're doing good!"

Myra moves your table back to its original position, gets off the table she was sitting on and thinks about what she wants to do next.