Subject No. 17 – The Runaway Muscle Monster
B woke to another ordinary morning. A 45-year-old PE teacher, 181 cm tall and 91 kg, he took pride in the solid, muscular build he’d maintained through years of training. As usual, he left the house early to head to school. The predawn streets were quiet—no cars, no people. He walked with a light, easy stride, earbuds in, moving to the rhythm of the music.
Then a black van passed slowly in front of him. It glided by, almost casually. But it seemed to pause for a moment. When B glanced toward it, the driver suddenly floored the accelerator and sped off. “Lost, maybe?” He shrugged it off and kept walking.
A little farther on, heavy footsteps sounded behind him. Before he could turn, massive figures swarmed him—men even bigger than B, bodies packed with muscle. Their faces were completely hidden behind black masks and caps. One clamped a hand on the back of his neck while another pressed a chloroform-soaked cloth over his mouth. Everything went dark.
The lab was cold and brightly lit under fluorescent lights. Beyond the one-way glass wall, Subject No. 17 lay in the observation chamber—stripped naked and secured to the metal floor. The compound had already been administered: a hyper-concentrated growth hormone mixed with a libido amplifier, delivered straight into the vein.
Researcher A checked the monitor and noted aloud,“Fifty minutes post-injection. Vitals stable. Awaiting initial response.”
Researcher B adjusted the cameras and replied,“Baseline weight 91 kg, excellent muscle mass. Growth projection high. Observation commencing.”
B’s eyes fluttered open. His head was thick and foggy from the lingering anesthesia. His bare skin pressed against the icy floor. Concrete walls on three sides, one massive glass panel on the fourth. Beyond the glass—nothing visible. Just a dark mirror reflecting his own naked body back at him: cock half-hard and hanging, muscles still ordinary.
“Ugh… where the hell am I…” He tried to sit up, but his limbs felt lead-heavy. Then a prickling heat began to spread slowly through his body, pulsing gently through his veins like liquid fire. “Haah… something’s… burning inside me… moving…”
Researcher A spoke calmly.“Core temperature up 1.5 degrees. Muscle cell activation confirmed.”
The change started in his chest—slow, lewd, irresistible. The thick slabs that had always been there began to swell beneath the skin, twitching greedily as they grew. Each fiber expanded, pushing the skin outward. His nipples reacted first—flushing dark red, stiffening into hard peaks, the surrounding skin prickling with unbearable sensitivity. Thin veins rose to the surface, heating the whole chest like a furnace. B’s hands moved on instinct, pinching the nipples hard and kneading the swelling muscle. Under his palms the pecs grew heavier, denser, the weight building steadily. “Nngh… fuck… my chest is blowing up… nipples are so fucking sensitive… every pinch makes my cock twitch… shit…”
The heat crawled to his shoulders and back. His shoulders widened gradually, the muscles around his neck rising and squeezing. His back thickened into a broad, dense wall, skin stretching tight over the deepening ridges. B twisted to reach behind him, fingers digging between the swelling slabs. Every touch sent shivers through him. “Haah… my back’s getting huge… these heavy slabs feel like they’re gonna tear the skin… fuck, just touching them makes pre-cum leak…”
Down his arms, the biceps and triceps swelled in slow, obscene pulses. Veins thickened across the surface; flexing sent waves of raw pleasure through him. Even the backs of his hands bulged, veins throbbing. His abs carved themselves deeper—eight blocks becoming ten, each one hardening into hot, rigid steel. B traced the grooves with his fingers, pressing deep. “Ah… my abs are cutting in one by one… so fucking hard… my whole stomach’s turning into one big erogenous zone… fingers sliding right in…”
His thighs reacted slowest but most lewdly. The front muscles thickened gradually, pressing immense weight against the floor. The inner thighs swelled, squeezing his cock and balls mercilessly. Calves and hamstrings ballooned too, turning his legs into monstrous pillars. The scale ticked upward steadily: 130 kg… 190 kg… 260 kg… 300 kg…
Researcher B noted analytically,“Muscle volume increase trending upward. Projected weight 310 kg. Growth rate stable.”
The changes to his cock were the most blatant, the most filthy pleasure. It started tingling, then slowly lengthened—30 cm, 50 cm—dragging across the floor. Thick veins roped across the shaft; the head flushed deep red and ballooned. Clear pre-cum oozed steadily from the slit. His balls swelled heavy as basketballs, pressing hard between his thighs, already leaking seed that puddled stickily beneath him. B reached down and stroked slowly. “Ah… my cock’s getting so long and thick… veins popping out everywhere… just touching it makes cum drip… my balls are so heavy… churning with seed… the smell’s everywhere…”
Erection built gradually but inexorably. The shaft rose, reaching toward 90 cm, 110 cm. Pre-cum poured like a hose, soaking the floor. Desire rose in a slow, overwhelming tide.
Then he looked at the glass. His transformed body stared back—swollen chest and abs, arms and legs ready to burst, monstrous cock dragging seed across the floor. And yet… he felt eyes on him. Nothing visible beyond the mirror, but the gaze was unmistakable, prickling his skin. The reality hit: he’d been taken. ‘They’re watching me… right now… seeing this naked body… the growing muscle… the leaking cum… everything.’ Shame mixed with a twisted, filthy thrill. His cock throbbed harder, spurting more pre-cum. “Haah… someone’s watching… this filthy body… my cock growing huge… cum dripping… they’re seeing it all… fuck, it’s making me even hornier… I want them to see more…”
Researcher A recorded,“Penile length 112 cm, girth 43 cm confirmed. Testicle volume 2.8× baseline. Initial pre-ejaculate volume 400 ml.”
B couldn’t hold back anymore. His massive hands gripped the cock—too thick for both to wrap around fully, girth like a waist—and began stroking slow and greedy. He pressed his thumb hard into the head, fingers sliding along the veined shaft. “Nngh… fuck… so thick my hands slip… the head’s swollen huge… every stroke leaks more cum… haah… you’re watching, aren’t you? My dirty jerking… the cum shooting… watch it all…” He sped up, kneading his balls roughly with the other hand; they churned audibly, pumping seed upward.
Researcher B stated flatly,“Self-stimulation initiated. Erection sustained at 100%. Ejaculation imminent.”
The first orgasm hit. “Aaaah—! Coming… shooting everything…!” B’s groan echoed through the chamber. Cum erupted in a geyser, slamming the glass wall. 2.4 liters of thick white seed splattered and ran down, puddling stickily on the floor. The smell was overpowering.
Researcher A noted,“First ejaculation volume 2.4 liters. Erection maintained. Second stimulation resuming.”
B panted and gripped again, stroking harder and faster. He twisted the head roughly, pumping the shaft like a piston. ‘They’re watching the cum smear the wall… they want more? I’ll give them filthier…’ The thought detonated his arousal. The second load blasted even harder—nearly 3 liters, hosing the glass until it was completely streaked white.
Researcher B reported,“Cumulative volume 5.5 liters. Additional muscle growth confirmed. Weight exceeded 340 kg.”
Third, fourth… for hours the cycle continued—slow at first, then endless. Hands aching from stroking, cum pooling ankle-deep. The cock stayed steel-hard past 120 cm.
Researcher A’s final entry:“Libido runaway sustained. Average interval 25 minutes. Total volume over 18 liters. Experiment successful. Continued observation required.”
B was lost completely in lust. Staring at his monstrous reflection, feeling the unseen eyes, he sank deeper. “Keep watching… my cock… my cum… watch everything… I’ll shoot more…” he muttered, gripping again. Pleasure built endlessly and exploded, cum overflowed without cease. This filthy runaway showed no sign of stopping.