Exactly as planned (Warning: Do not continue unless you are willing to be powerless, and to have anything happen to you)

"We'll have to give her a distraction," says Buldar, "Give her something nice to remember."

"I don't think any of us three can do it," says Cocephalos, gesturing to the other centaurs, "The geometry just won't work out. Today might be the first time I've started to regret having four legs. You'll have to do it."

"This is your triumphant day though!" says Buldar, "Besides, who would perform the procedure?"

"We'll just call someone in," replies the centaur, "Maybe an imp, they're very good at this sort of thing."

Buldar keeps hold of you and grabs your sword. He hands each off to a different centaur. Your sword is taken away, but you're held stock still while Buldar walks out of sight into another room. You hear conversation, then the sound of things being moved around. Buldar returns with a strange creature you've never seen before. It's smaller than a human, maybe 4 feet tall, with very long limbs that are bowed as it walks. It is reddish-brown in color. Buldar is carrying a large metal case, which he sets down in a place the creature designates.

The creature wordlessly approaches you, investigating your body. It coldly grabs you, squeezing around, performing some inscrutable calculation in its head. It wraps its bony fingers around your testicles, then holds them along your penis's shaft. It squeezes painfully a few times. It takes out several pieces of wire and manipulates them around your genitals, making markings and bends in the metal to track various measurements. Satisfied, it gestures to Buldar and says something in a guttural language you don't understand.

Buldar seats himself on a low stool and pulls you onto his lap. He gropes your body, feeling you all over. His touch is entirely unlike that of the strange creature. You want to recoil from it in disgust and discomfort, but you find feelings of arousal and submission rising up from a primal part of you. He squeezes your ass, then plays with your nipples. You shiver. Buldar stands you up as he removes his clothing, revealing his cock. It's not as large as the centaur's, but it is several times larger than any penis you had ever seen before this ordeal. He sits back down and pulls you with him, guiding your ass so as your knees begin to bend his glans is pressed up against your asshole. He leaves you there for a little while, until your legs begin to burn, then he grabs your waste and slams you down, his hard penis driving all the way into your body in one single motion. The fourteen inch shaft buries itself to the hilt, and you find your ass resting on his lap. The pain and pleasure return immediately. Before you're fully adjusted he lifts you up, then slams you back down again. Incredible waves of pleasure emanate from your stretched rectum and colon. He begins to slam you up and down, practically jacking himself off with your tight hole, the rest of your body dragged along. You subconsciously clench your ass, trying to grip him as tightly as possible. It hurts a little more, but it feels so good. As he continues to fuck your little body, the pleasure grows and grows until it's all you can feel. Despite everything that happened earlier, you begin to feel that familiar pressure build up inside of you. Your clit is rock hard.

Suddenly, Buldar slows his pace. Thrusting firmly but carefully into your hungry hole. Every thrust leaves you tantalizingly close to bursting, but never takes you all the way there. The creature has arranged a number of tools and objects, and is now standing directly in front of you as you bounce deliciously on Buldar's rod. A sort of harness is attached to your waist, and then some sort of platform is placed below your testicles, separating them from Buldar's. The creature erects a strange scaffold our your genitals. As the scaffold nears completion, Buldar stops moving you and begins thrusting with his own hips, plowing you from underneath. The creature maneuvers the scaffold so your testicles are held firmly in place. You see an open circle on each side of it, each of you balls pressed up against one. As the creature turns away from you for a moment, Buldar picks up his pace. You almost scream with joy as he reams you, slamming your little pussy with reckless abandon. The pressure builds to a breaking point as the creature turns back around, something glowing red hot in its hand. You barely notice as it lowers its tools to your groin, lining up the glowing thing with the holes in the side of the scaffold. Your body sings with delight as Buldar's relentless pounding makes you burst, and a huge load of cum begins to gurgle out of your tiny erect penis. The cum hasn't even made it out of your shaft when you feel a searing, overpowering pain in your testicles, and your head jerks down to see a metal rod has been driven straight through both your balls. A faint smell of burnt flesh wafts through the air as your worthless cum squirts all over you and you pass out from the pain.