Chapter 4: Anal Expansion
The ache in Evelyn’s right glute was a raw, screaming thing. Every step sent jagged bolts of fire radiating from the deep muscle tear she’d inflicted during yesterday’s desperate squat session. It wasn't the familiar, deep chemical burn of Vivian’s serum in her left ass cheek – that was a constant, pulsing ember. This was different. Sharper. Hotter. A grinding, tearing agony that made her hobble. Yet, beneath the searing pain vibrating through the damaged fibers of her right glute, something else hummed. A faint, terrifying echo of the power Vivian had forged in the left. A cellular hunger. Proof the serum was in her blood, demanding balance. Demanding symmetry.
The sterile chill of Vivian’s treatment room hit her like a physical blow. Vivian stood near a new apparatus – a sleek, padded metal inversion table, tilted at a severe angle, its ankle clamps open like waiting jaws. Vivian’s gaze cut through Evelyn’s attempt at composure, landing instantly on the subtle hitch in her gait, the way she favored her dominant left side. Her eyes, cold and analytical, scanned Evelyn’s leggings, lingering on the pronounced swell of the hypertrophied left glute and the slightly less defined, clearly inflamed right.
"Report," Vivian commanded, the single word echoing in the clinical space. She didn’t gesture towards the usual table. Her focus was locked on the inversion rig.
"Trained glutes. Heavy squats." Evelyn’s voice was hoarse. "Focused… focused on the right. Like you said. Made it burn." She swallowed, the memory of that tearing agony fresh. "It… it tore. I think. Deep."
"Good," Vivian said, a flicker of something dark in her eyes that might have been approval. "Provocation achieved. Damage primes the tissue for accelerated reconstruction." She tapped the thick syringe resting on a tray beside the table. It wasn’t amber this time. It was viscous, almost opaque, a muddy grey. A larger bore needle gleamed wickedly. Beside it lay a heavy glass plug, thickly ribbed and glistening with lubricant. "This concentration," Vivian continued, her voice dropping lower, colder, "requires direct access. Deep intramuscular injection into the gluteus maximus insertion point. Proximity to the anus is optimal." Her gaze locked onto Evelyn’s, utterly devoid of warmth. "Remove your clothing. Position yourself on the inversion table. Face down. Ankles secured."
The raw specificity, the clinical detachment describing such an intimate violation, sent a tremor through Evelyn. Fear, cold and sharp, prickled her skin. But the familiar heat, the treacherous pulse between her legs, flared hotter in response to Vivian’s absolute command. The promise of deeper penetration, of Vivian going further, ignited the shameful addiction. She obeyed, stripping silently, her movements stiff with pain. The cool metal of the inversion table shocked her bare stomach and thighs as she climbed onto it. Vivian moved with predatory efficiency, securing the padded clamps around Evelyn’s ankles with sharp clicks. The angle was steep. Evelyn’s head swam as the room tilted, her legs raised high above her torso. Her ass, with its lopsided swell and the raw injury in her right cheek, was thrust obscenely into the air, completely exposed. Vulnerable. Open. The cool air of the room brushed against her exposed anus, making her clench instinctively.
Vivian approached. Evelyn felt the chill of the alcohol swab on her right buttock, lower this time, dangerously close to her asshole. The cold sting was brief. Then came the terrifying, impersonal grip of Vivian’s latex-gloved hands, spreading Evelyn’s ass cheeks wide apart, exposing the tight pink pucker completely. Evelyn whimpered, the sound muffled against the padded table. Vivian’s thumb, slick with lubricant, pressed firmly against Evelyn’s anus. Not probing. Just pressure. Cold, clinical pressure.
"The sphincter must relax," Vivian stated flatly. "Resistance compromises injection depth and increases tissue trauma." Her other hand, lubricated fingers glistening, moved lower, finding Evelyn’s soaking cunt. Two fingers plunged deep without warning, hard and unforgiving. Evelyn gasped, arching against the restraints as Vivian’s fingers fucked brutally into her pussy, the rough texture of the latex scraping her inner walls. "This facilitates relaxation," Vivian said, her voice chillingly matter-of-fact as she pistoned her fingers, the wet sound obscenely loud. She crooked her fingers, pressing hard against Evelyn’s G-spot. Pleasure, sharp and unwanted, jolted through Evelyn’s core, warring with the deep tear in her glute and the terrifying exposure of her asshole. Her sphincter fluttered involuntarily under Vivian’s thumb.
"Good," Vivian murmured. The thumb pressed harder, then began to slowly, inexorably, push in. The stretch was immediate, intense. Evelyn cried out, a ragged sound torn from her throat, as the thick digit breached her tight ring of muscle. Vivian worked it deeper with cold precision, stretching her open. "Deep penetration requires preparation," Vivian stated, twisting her thumb slightly, making Evelyn sob. "Breathe. Accept it." Vivian withdrew her thumb. Before Evelyn could even gasp in relief, the cold, slicked tip of the thick glass plug pressed against her stretched entrance. It was massive. Unyielding. Vivian pushed. Evelyn screamed as the rigid glass bulb forced its way past her resisting sphincter, stretching her wider, deeper than the thumb. It burned. It felt like she was being split open. Vivian pushed relentlessly until the widest part of the ribbed plug lodged firmly inside her, the flared base sealing her shut. Evelyn panted, tears leaking from her eyes, her asshole throbbing around the intrusive cold glass. Vivian’s fingers continued their brutal rhythm inside her pussy, somehow making the violation of her ass feel even more profound.
"Stable access," Vivian declared, her gaze fixed on the area immediately beside the plug’s base, where Evelyn’s right glute muscle met the crease of her ass. Vivian’s free hand, the one not buried in Evelyn’s cunt, picked up the syringe. The needle looked monstrous. Evelyn felt Vivian’s fingers probing the muscle beside her violated asshole, finding the precise spot. Pinching. Pulling tissue taut. Isolating the damaged insertion point.
The needle pierced.
Evelyn’s scream was choked this time, muffled by the table and the overwhelming sensation of being filled and invaded from both ends. The needle burrowed deep, angling beside the glass plug, plunging towards the core of the torn muscle in her right glute. Vivian depressed the plunger slowly, steadily. The grey serum, thick as sludge, flooded into the inflamed, damaged tissue.
The burn was apocalyptic. Not chemical fire, but acid and ground glass. It seared through the fresh tear, igniting the damaged nerve endings with white-hot agony. Evelyn convulsed, her body straining against the inversion straps, her asshole clenching spasmodically around the cold glass plug. Vivian’s fingers inside her cunt pistoned harder, faster, grinding against her G-spot with cruel precision. She leaned close, her lips almost brushing Evelyn’s ear, her voice a venomous whisper that cut through the haze of pain. "Feel it, Evelyn. Feel the serum flood that greedy, torn muscle. Feel my plug stretching your filthy asshole wide open. This fire… this stretch… this is what sculpts you. This is what will make your glutes hard and heavy enough to split every pair of leggings you own. You want that, don’t you, you desperate, muscle-obsessed whore? To have everyone stare? To know it’s my serum, my treatment, my plugs filling you up that made you into this fucking monument?"
Vivian punctuated her words with a brutal thrust of her fingers and a final, hard push of the plunger, injecting the last of the viscous grey serum deep into Evelyn’s ravaged glute. The collision of sensations was catastrophic. The acid burn in her muscle fused with the brutal fullness of the plug stretching her asshole and the punishing friction inside her pussy. Shame, pain, and a terrifying, degrading arousal detonated.
"YES!" Evelyn shrieked, the word ripped from her soul. "FUCK YES! MAKE ME SPLIT THEM! MAKE THEM ALL SEE! YOUR SERUM! YOUR WHORE!" Her body locked, rigid. Her cunt gushed around Vivian’s driving fingers. Her asshole convulsed rhythmically, clenching and releasing around the thick glass plug in time with the seismic pulses of her climax. The fire in her right glute flared white-hot, merging with the orgasm into a single, devastating wave of annihilation. She saw only white light and Vivian’s cold, triumphant eyes.
Silence. Heavy. Broken only by Evelyn’s ragged, wet gasps and the soft hum of the clinic. Vivian slowly withdrew her fingers from Evelyn’s soaked cunt. She pressed gauze hard against the injection site beside the glass plug, the pressure sending fresh jolts of deep agony through Evelyn’s spent body. The inversion table whirred, slowly returning Evelyn to a horizontal position. The sudden shift made the plug shift inside her, a shocking reminder. Vivian unfastened the ankle clamps. "The plug remains for two hours," she stated, peeling off her gloves. "It maintains dilation for optimal serum dispersion. Move minimally. Hydrate." She tossed a small towel onto Evelyn’s trembling stomach. "Your symmetry progresses. Train glutes lightly tomorrow. Stimulation, not provocation. The serum is working."
Evelyn stumbled off the table, legs weak, the heavy glass plug an impossible, burning weight lodged deep in her ass. Every tiny movement sent fresh awareness of it, of the deep, corrosive burn in her right glute, and the slick mess between her legs. Vivian was already washing her hands, her back turned. Evelyn pulled on her leggings with trembling hands, the fabric stretching tight over her lopsided, inflamed ass. The plug shifted inside her as she moved, a constant, humiliating pressure. She could feel its rigid shape outlined obscenely under the thin fabric. Vivian’s words echoed: Split every pair of leggings. Evelyn looked down. The enhanced left cheek strained the fabric, round and hard. The right, now swollen with fresh serum and inflammation, pressed just as hard. And between them, the unmistakable bulge of the plug’s base.
She walked out of the clinic, every step a careful negotiation with the intrusion in her ass and the fire in her glutes. People passed her on the street. Did they see? Did they know? The shame was a crushing weight. But beneath it, coiling deep in her gut, hotter than the serum’s burn, was a terrifying thrill. Vivian’s plug. Vivian’s serum. Vivian’s creation. She was walking proof. Owned. Filled. And undeniably, dangerously, transformed. The fire in her ass wasn't just pain anymore. It was a brand. A promise. And a terrifying, exhilarating addiction.
The fire in her ass wasn't just pain anymore. It was a brand. A promise. And a terrifying, exhilarating addiction. Each step down the sterile clinic hallway felt alien, the thick glass plug a cold, unyielding anchor lodged deep inside her rectum, shifting minutely with every shift of her hips. The sharp, corrosive burn Vivian’s latest serum had ignited in her freshly torn right glute muscle screamed with every footfall, a counterpoint to the heavy, stretched ache radiating from her sphincter. Her leggings clung obscenely, the enhanced left cheek a hard, defined globe, the right swollen and inflamed, the rigid outline of the plug's flared base unmistakable beneath the thin fabric. She kept her eyes glued to the scuffed linoleum, cheeks blazing hotter than the serum burn. Split every pair of leggings. Vivian’s whisper echoed, vile and thrilling.
Outside, the mundane afternoon light felt shocking, invasive. A woman pushing a stroller smiled vaguely in her direction. Evelyn flinched, convinced the woman’s gaze dropped straight to her ass, saw the obscene bulge, knew about the plug, the serum, the violation. She clutched her gym bag like a shield against her stomach, hurrying towards her apartment building. The plug pressed insistently against her inner walls with each stride, a relentless reminder of being forcibly opened, filled. It wasn’t just the size; it was the coldness, the impersonal smoothness of the glass, a stark contrast to the organic heat it provoked. Her cunt, still slick and sensitized from Vivian’s rough fingers, pulsed treacherously, sending tendrils of unwanted arousal coiling through her lower belly, tangling with the pain and the deep-seated shame. She felt exposed, monstrous, yet terrifyingly alive.
Her apartment building lobby offered no sanctuary. Mrs. Henderson from 3B was wrestling grocery bags out of the elevator. "Evelyn, dear! Haven't seen you this week! Still whipping those gym bunnies into shape?" The older woman’s cheerful voice boomed, echoing off the tiles. Evelyn forced a brittle smile, her body rigid, hyper-aware of the plug shifting inside her as she shifted her weight. "Always, Mrs. H. Just… busy." She practically dove into the waiting elevator, jamming the button for her floor. "You look flushed, dear! Must be working hard!" Mrs. Henderson called as the doors slid shut. Evelyn leaned back against the cool metal wall, squeezing her eyes shut, the plug feeling impossibly large, the serum burn in her right ass cheek a white-hot coal. They all see. They all know. The thought was irrational, paralyzing. The elevator chimed. Her floor.
Unlocking her door felt like an eternity. Inside, the familiar scent of lavender cleaner did nothing to soothe. She slammed the door shut, bolted it, and leaned heavily against the wood, gasping. Sanctuary. But the intrusion came with her. The plug. The burn. Her reflection in the hallway mirror caught her – flushed face, wild eyes, the obscene, undeniable distortion of her leggings over her ass. Vivian's creation. Vivian's property. The degradation warred violently with a sickening jolt of pride at the sheer, undeniable mass her glutes now possessed. She needed it out. Now. But Vivian’s command echoed: Two hours. Optimal dispersion. Moving minimally felt impossible. The need to squat, to push, to expel the cold invader was overwhelming. Yet… that very pressure, that fullness… it stoked the embers Vivian had lit in her cunt.
She stumbled towards the bathroom, not for the shower, but for solitude. The mirror above the sink offered a brutal view. She peeled the sweat-damp leggings down with trembling hands, wincing as the fabric dragged over her inflamed, lopsided ass cheeks. The plug’s clear glass base gleamed against her skin, nestled tight against her stretched anus. Seeing it, actually seeing the thing buried inside her, stole her breath. It was massive. Degrading. She turned, craning her neck, trying to see the injection site Vivian had violated beside it, the skin red and angry. Proof. She traced the inflamed area lightly. The serum burn flared viciously in response, a molten spike driving deep into the muscle. A choked moan escaped her, part pain, part something darker. Her fingers, seemingly of their own volition, drifted lower, sliding through the slickness coating her inner thighs, finding her swollen clit.
It was like touching a live wire. Pleasure, raw and electric, jagged from the oversensitivity Vivian’s fingers had left, jolted up her spine. She gasped, her hips jerking forward involuntarily. The movement shifted the plug inside her ass, grinding the thick glass ribs against her inner walls, pressing firmly against that deep, hidden spot. A strangled cry tore from her throat – pain from the plug’s movement and her inflamed muscle, fused with a bolt of shocking, intense pleasure radiating from her prostate. "Fuck!" she hissed, fingers circling her clit faster, rougher. The conflicting sensations were maddening, addictive. She bucked against her own hand, the plug shifting again, another wave of that deep, internal pressure-pleasure surging through her. Vivian’s face filled her mind – the cold calculation, the absolute control, the feel of those latex fingers stabbing into her cunt while the needle burned her ass. ‘You desperate muscle whore.’
Her other hand slapped back, not to remove the plug, but to press against its base, pushing it deeper, harder against that spot inside her rectum. The stretch burned. The pressure was immense. It hurt. It felt like being speared. And it sent pure, undiluted lightning up her cock. "Oh god, oh fuck, YES!" she screamed, her voice ragged, echoing off the tiles. She fucked herself back onto her own pushing hand, driving the plug brutally deep, while her other hand mashed her clit into oblivion. The serum burn in her right glute became a furnace, merging with the anal pressure and the frantic friction on her clit into a single, devastating crescendo. It wasn't just coming; it was detonating. Her vision whited out as her body convulsed, her asshole clamping down in violent spasms around the thick glass invader, her cunt pulsing empty air, her scream dissolving into wordless, animalistic cries. Wave after wave of brutal ecstasy, inextricably tied to violation and pain, tore through her.
Then, silence. Panting. Trembling. The cold glass plug heavy and intrusive inside her ravaged ass. The serum burn a dull, deep roar in her muscle. The shame crashed over her like ice water, cold and suffocating. What had she done? What had she become? Needing Vivian’s torture, fucking herself on the instrument of her degradation, climaxing from the very violation that humiliated her. The image in the mirror was grotesque: sweat-slicked, red-faced, legs shaking, a thick glass plug protruding from her reddened asshole. Vivian’s filthy words resonated, true and damning. Desperate muscle whore. The exhilarating high of the climax evaporated, leaving only the brutal reality, the profound self-loathing. The trembling intensified, wracking her entire frame. Her breath hitched, a strangled sob catching in her throat. The weight of it all – the pain, the degradation, the loss of control, the terrifying addiction – collapsed onto her shoulders. Her legs gave way. She crumpled onto the cold bathroom tiles, the plug jolting painfully inside her as she hit the floor. Great, heaving sobs tore from her chest, raw and uncontrollable. She curled into a tight ball, her lopsided, branded ass exposed, the plug a constant, humiliating reminder, as she wept.
The cold tile bit into her hip and shoulder as Evelyn sobbed, her body shaking with the aftermath of humiliation and violent release. Tears blurred the harsh bathroom light, the thick glass plug a cold, alien weight anchoring her to the floor, to Vivian’s control. Each ragged breath made it shift minutely inside her ravaged rectum, a fresh spark of discomfort cutting through the deep, corrosive burn still pulsing in her right glute muscle. Vivian's words – desperate muscle whore – echoed like a curse, confirming the terrifying truth she couldn’t escape: the pain, the violation, the degradation were the fuel, the sickening price of the power Vivian offered. The power she craved more than oxygen.
Time crawled. The sharp edges of despair eventually dulled, replaced by a hollow numbness and the persistent, demanding throb from her ass and the searing ache in her glute. Vivian’s clinical instruction – two hours – surfaced through the fog. It felt like an eternity. She couldn’t stay crumpled on the floor. Gingerly, every movement agony, she pushed herself up. The plug shifted heavily, a brutal reminder. Standing felt precarious. She avoided the mirror, focusing only on the shower, craving the scouring heat to wash away the sweat, the tears, the phantom feel of Vivian’s latex, the slickness between her thighs. She needed oblivion.
The water was scalding, a physical assault she welcomed. It pounded down on her tense shoulders, her branded back, her inflamed ass. She gasped as the heat hit the swollen injection site beside the plug’s base, the serum burn flaring hot-white for a moment before the water’s steady beat tempered it to a deep, resonant throb. She braced her hands against the slick tiles, head bowed, letting the steam envelop her. The plug felt different under the water – colder, heavier, more intrusive.
She reached for the soap, lathering her hands roughly. She scrubbed her arms, her neck, avoiding her ass, avoiding the plug. Her hands moved over her stomach, then higher, over her ribs. Her fingers brushed the underside of her small, firm breasts. A strange, sharp sensitivity made her flinch. She paused, frowning beneath the spray. Had she bruised herself? She soaped her hands again and lifted her left breast, cupping it. The skin felt tauter than usual, stretched thin. Fuller. The nipple, usually soft when not aroused, was erect and hypersensitive, the peak hard as a pebble against her soapy palm. A tremor ran through her. It wasn’t just sensitive. It felt… heavier. Denser. She squeezed gently, experimentally. A wave of intense sensation, almost painful in its sharpness, radiated from the nipple deep into the tissue. Not just arousal. Growth.
Panic, cold and sharp, sliced through the steam. She dropped her hands, backing away from the water spray as if scalded. Her heart hammered against her ribs. No. No, not there. She looked down. Water streamed over her torso. Her breasts, always modest, high, and firm from her physique, looked… different. Swollen. Rounder. The areolas seemed slightly darker, stretched. The nipples stood out, thick and stiff. She lifted them again, the weight undeniable now, the tissue beneath her fingers feeling thick and engorged, like muscle pumped full of blood after a brutal set, but… permanent. Vivian’s serum. It wasn’t just targeting her glutes. The realization hit her like a physical blow. The systemic spread Vivian had hinted at. It was rewriting her. Remaking her. Even here. "You bitch," Evelyn whispered, the sound lost in the rush of water. "You fucking… cunt." The violation felt total, absolute. Her body wasn't hers anymore. It was Vivian's experiment, Vivian's sculpture. Every curve, every ache, branded.
She turned off the water abruptly. The sudden silence roared. Dripping, shivering despite the residual heat, she stepped onto the bathmat. She avoided looking down, focusing on the towel. She wrapped it around herself, the rough terrycloth grazing her hypersensitive nipples, making her gasp. Every nerve ending felt raw. She forced herself to turn towards the fogged mirror. With a trembling hand, she wiped a clear swath.
The reflection stunned her. Her face was flushed, eyes shadowed. But her body… Below the towel, the outline was unmistakable. Her glutes, left and right now visibly fuller – the left sculpted and hard, the right inflamed but catching up – strained the towel’s lower edge. Above the towel, the swell of her breasts pushed against the fabric. They weren't huge, not yet, but the change was undeniable. Fuller. Rounder. Heavier. The tops were fuller, pushing against the towel where before it might have hung loosely. They had a slight, unfamiliar weight that pulled them downwards just perceptibly. Her nipples, hard and dark, outlined the fabric obscenely. A small, but undeniable boob grow. A side effect. Vivian’s serum coursing through her, reshaping her without consent, beyond her control. A fresh wave of terror warred with a terrifying, perverse fascination. She looked… powerful. Undeniably changed. Owned.
Her phone buzzed violently on the counter, shattering the heavy silence. Vivian’s name flashed on the screen. Evelyn stared at it, her hand hovering, damp towel clutched tight. The serum burned in her glute. The phantom pressure of the plug lingered in her ass. Her new breasts ached with strange sensitivity. Vivian’s voice slithered into her mind: ‘Symmetry progresses. Train glutes lightly tomorrow. Stimulation. Not provocation.’ The command was absolute. The addiction was deeper than muscle. It was cellular. Her body screamed for Vivian’s approval, Vivian’s next violation. With a trembling finger slicked with condensation from the mirror, she swiped to answer, bringing the phone to her ear. Her voice, when it came, was a hoarse whisper, thick with unshed tears and the terrifying thrill of surrender. "Vivian?" The name itself felt like a confession. A plea.s