Chapter 5: The Volunteer
The sterile chill of the recovery room bit into Bree’s sweat-slick skin the instant she pushed through the door, a tremor running through her thighs that was equal parts exhaustion and something else she couldn’t name. The door clanged shut behind her, metallic and final. Antiseptic bit at her nose, but beneath it—her own scent clung, the musk of climax that refused to be erased. Across the room, Evelyn stood beside the glowing console bank, her jaw locked, voice taut. “We can’t provide manual stimulation to our test subjects. You know what you did today with Bree cannot happen again.”
Humphrey didn’t even look up from the monitors. His voice came out low, controlled, precise. “Suboptimal modulation profile. Requires refinement. Olsen’s session parameters need immediate adjustment.” His fingers flicked over the console, scrolling through Bree’s neural readouts. “Fine,” he said finally, glancing up with that same detached authority that made her want to claw him and kiss him in the same breath. “Subject Bree can administer the manual stimulus to Olsen. She’s already proven effective.”
Effective. The word hit her like a slap. Bree’s breath caught, fury flashing bright—but tangled with something molten and dangerous that coiled low in her belly. “Effective?” she echoed, her voice raw, trembling. “You think I’m—what? A lab tool now? Another machine you can just assign?”
Humphrey turned, slowly, the movement deliberate. His gaze swept her, analytical, impersonal—but beneath the cold glint of his glasses, something flickered. “You demonstrated an enhanced response pattern when emotionally engaged,” he said. “You’re uniquely capable of translating that sensitivity into controlled stimulation. It’s an efficient use of resources.”
Her laugh came out sharp and breathless. “Efficient,” she spat. “You talk about me like I’m a fucking piece of equipment, and you think that’s going to make me want to touch someone else for you?” The tremor in her voice wasn’t just rage—it was the shiver that came from imagining it. Olsen restrained, the machine pistoning into him, Humphrey’s intense gaze fixed on her as her fingers wrapped around Olsen’s cock, stroking him while the machine pounded him. The visceral contradiction – outrage warping into a dark, unwanted thrill – made her stomach lurch. Her pussy clenched, a fresh wave of wetness seeping out, undeniable and shameful.
Humphrey’s jaw twitched, a nearly invisible pulse of muscle. “You misunderstand, Subject Bree,” he said quietly. “It’s not desire I’m requesting. It’s discipline.”
But that word—discipline—landed differently. It made something deep inside her tighten, that dark pulse she tried to bury quickening. “You think I don’t have control?” she shot back, stepping closer, the distance between them charged with a static that made her skin prickle. “You think you can program every fucking reaction I have?”
Evelyn moved, uneasy, her voice a tremor of warning. “Alistair, this is going too far—”
Humphrey cut her off with a glare. “This is science, Dr. Park. We record the truth, not coddle it.” He looked back to Bree, the air between them humming. “And the truth is, Bree, your data shows extraordinary compatibility with the machine and our protocols and your pleasure response is proven to be exceptional. If Olsen’s experience is modulated by your manual input, the system will adapt more efficiently.”
She swallowed, the clinical words wrapping around her like a command. “Manual input,” she repeated softly. “You mean my hand. On him.”
His expression didn’t change—but his eyes lingered on her mouth. “Yes.”
Something flickered through her—anger, humiliation, and, beneath it, a deep, pulsing heat that made her knees weak. “You don’t even ask me,” she whispered, voice shaking. “You just tell me. Like you know I’ll say yes.”
Humphrey’s voice dropped lower, almost a growl. “You wouldn’t still be here if you weren’t capable of following orders.”
The words sliced through her resistance. Capable. Following orders. Her pulse pounded in her throat, traitorous. He believed she could assist him in this way and it wouldn’t jeopardize the integrity of the study. He was trusting her to do what he had done. He believed she could control pleasure itself—channel it, direct it, weaponize it. The thought made her dizzy.
Evelyn stepped closer, her tone sharp now. “Alistair, stop it. You’re blurring lines that shouldn’t—”
“Lines,” he interrupted, his eyes still locked on Bree’s, “are what we study here.” He stepped forward, closing the last inch between them. “Bree, when you grabbed my hand, when you lost control—your readings went off the chart. You were perfect. And now you can apply that control outward. Olsen’s data depends on it.”
Her lips parted, breath shallow. “And you trust me to do that,” she murmured. “You trust me with that much power.”
Humphrey’s voice softened to something that sounded almost human. “I do.”
For a heartbeat, the sterile hum of the lab disappeared. All she could hear was the pounding in her ears, all she could feel was the phantom weight of his gaze—his approval, his ownership. She should have hated it. Instead, it made her thighs press together, heat seeping out of her, shame and desire warring in every breath.
“Logical,” she whispered, almost mocking. “You keep saying that word. You think any of this is logical?”
“It will be,” he said simply. “Once you stop fighting it.”
Her mouth trembled with a half-formed retort, but nothing came. His nearness was suffocating; his calm, infuriating. Every time he spoke, she wanted to scream—and every time he ordered, her body obeyed in ways that terrified her.
Evelyn broke the silence, voice clipped. “Alistair, this isn’t research anymore. This is dangerous experimentation.”
He didn’t look at her. “Protocol is established,” he said. “Subject Bree, report to Prep Bay Omega in two days. You’ll receive Olsen’s baseline parameters there.”
Something inside Bree cracked. She stared at him, chest rising and falling, the burn of fury blurring into a desperate, aching pulse between her thighs. “And what if I don’t?” she challenged.
Humphrey’s gaze met hers—hard, dark, unreadable. “Then you’ll prove me wrong,” he said quietly. “But you won’t.”
She hated him, and yet, she still wanted his hands on her again. She wanted to punch his face and sit on it in almost equal measure. And that, more than anything, terrified her.
The sterile walls seemed to tilt around her as she turned on her heel, heart hammering, fury burning away into a sick, slick arousal that left her trembling. The door slammed open with a deafening crash, her breath ragged as she stormed out, her pulse still echoing with the sound of his voice—You’ll prove me wrong.
Bree stared at his back, the sterile white walls seeming to close in. The trembling in her legs intensified, but it was no longer just from exhaustion. Burning with fury, drowning in a sickening wash of illicit arousal, she whirled and slammed the recovery room door shut, the crash echoing down the corridor as she stormed away, her cunt dripping with every furious step.
The sterile hallway lights glared down, bleaching the world into harsh angles and shadows that seemed to mock her trembling legs and the slick heat pooling between them. She pressed her thighs together hard, trying to crush the unwanted pulse, the phantom memory of Humphrey’s cold latex fingers circling her clit while the machine pistoned her asshole raw. "Fucking bastard," she hissed under her breath, the words tasting like ash, yet her nipples tightened against the thin fabric of her recovery gown. She needed a shower, needed to scrub his detached scrutiny and her own treacherous response off her skin, needed oblivion. Turning a corner sharply, she disappeared from view, leaving only the fading echo of her angry footsteps and the thick scent of her own conflicted need hanging in the antiseptic air.
A few hours later, the SPRINT observation room was silent except for the low, persistent hum of dormant machinery and the soft whir of cooling fans. Dr. Alistair Humphrey sat alone amidst the bank of monitors, the sterile white light casting sharp shadows on his face. On the primary screen, Bree’s first session played: her body arching violently, mouth open in a soundless scream as the thick polymer shaft plunged relentlessly into her pussy, stretching her obscenely wide. Humphrey leaned forward, elbows on the console, his gaze fixed not on the biometrics scrolling beside the feed, but on Bree’s face contorted in agony and ecstasy. He imagined pinning her wrists above her head, feeling the frantic flutter of her pulse against his fingers, her breath hot and ragged against his neck. He pictured his cock, thick and hard, replacing the machine’s shaft, fucking into that tight, dripping cunt with brutal, possessive strokes, making her scream his name instead of wordless pleas.
A muscle jumped in his jaw. With deliberate, almost clinical movements, he tapped a command. A second monitor flickered to life beside the first. This feed showed Bree’s second session – the one where he’d intervened. Here, the machine’s thick piston shaft was buried deep in her clenching hole, pistoning with the same brutal rhythm. His own gloved hand was visible, pressing firmly against her swollen clit, fingers working in cruel, precise circles. He watched his past self on screen, observing Bree’s writhing form with detached intensity, while his present self felt a familiar, insistent pressure building in his groin. The juxtaposition was obscene, hypnotic: Bree being fucked raw in her cunt on one screen, while simultaneously being stretched and violated in her ass on the other, his hand manipulating her pleasure-pain threshold on both.
His breath hitched, becoming shallow. He unzipped his trousers slowly, methodically, his eyes never leaving the monitors. His hand slipped inside, finding his cock already thick and straining against his briefs. He freed it, the cool air of the lab a brief shock against heated flesh. His gaze flickered between the two feeds: the Bree on the left monitor, her pussy stretched obscenely wide around the thick shaft, her face a mask of terrified ecstasy; the Bree on the right, her asshole swallowing the piston with wet, slapping sounds, her body jerking under the dual assault of machine and his gloved fingers. He wrapped his hand around his own hard length, the grip tight, almost punishing. He began to stroke, slowly at first, his thumb rubbing over the slick head in time with the rhythmic thrusts visible on both screens.
"Look at you," he murmured, his voice low and thick, devoid of its usual clipped precision. "Taking it. Needing it." His strokes quickened, syncing with the machine’s relentless pace on the monitor showing her cunt being fucked. He watched his past self press harder against her clit on the other screen, watched Bree’s mouth form a silent, desperate 'O' as her back arched impossibly high. "That's it," he breathed, his own hips pushing up into his fist. "Cum for the machine. Cum for me." His hand moved faster, rougher, the sound of skin on skin loud in the silent room, echoing the wet slaps from the speakers.
He focused on the precise moment on the ass-fucking feed where her body locked, her hole clenching violently around the invading shaft as her orgasm tore through her, mirrored almost simultaneously on the cunt-fucking feed as she screamed, her body convulsing. "Fuck!" Humphrey gasped, his own climax hitting him like a physical blow. Thick pulses of cum spurted hotly over his clenched fist and onto the console below, his body jerking uncontrollably as he watched Bree’s recorded ecstasy play out on the glowing screens. He slumped back in the chair, breathing heavily, the monitors still displaying Bree’s violated, trembling form in dual angles of brutal completion.
The sterile air hung thick with the pungent scent of his release and the ghostly echoes of her screams. He stared at the screens, spent but utterly transfixed, the cold satisfaction of data acquisition warring with a deeper, hungrier void the orgasm hadn't filled.
Humphrey wiped the cooling mess from his hand and the console with a sterile wipe, the clinical rasp of paper loud in the silent room. He tossed the crumpled wipe aside, its stark whiteness now soiled, a visual echo of the violation replaying on the screens. His eyes, sharp and unblinking despite the recent release, snapped back to the dual feeds, specifically zeroing in on the moment of Bree’s explosive climax during the anal session – his session. He leaned forward, elbows digging into the console edge, fingers steepled before his lips, scrutinizing the frozen frame just before she shattered.
On the screen, his gloved thumb was a hard, deliberate pressure against her engorged clit; the thick machine shaft was buried to the hilt in her straining asshole, stretching the puckered ring obscenely taut. “Freeze frame 17.43,” he murmured, voice gravelly. He magnified the image, focusing on her face: eyes squeezed shut, mouth a distorted oval of pure, agonized ecstasy, sweat-slicked skin pulled tight over the cords of her neck. “Physiological markers: heart rate 182 bpm, cortisol spike concurrent with endorphin flood… neural load critical.”
He rewound a few seconds, letting it play at quarter speed. The machine shaft pistoned out, then slammed back in with brutal force; simultaneously, his thumb ground a hard, deliberate circle. Bree’s body jolted, a full-body spasm. “Correlation,” Humphrey breathed. He rewound again. Played it slower. The shaft thrust deep. His thumb pressed. Her back arched violently off the platform, a silent scream tearing from her throat. “Synchronous sensory input. The peak coincides exactly with the combined mechanical penetration depth and the maximum pressure application.” He isolated the audio, amplifying her ragged cry until it filled the observation room: a raw, guttural sound, equal parts terror and surrender. "Oh FUCK! NOW! DR HUMPHREY!"
Not the machine. His name. His action. His pressure. The salient variable piercing through the noise of the machine's brutality. A fierce, possessive satisfaction, colder and deeper than any orgasm, settled in his gut. He hadn't just observed; he had orchestrated her unraveling, his hand the scalpel that dissected her pleasure from the pain. He needed to replicate this. Layer by layer, he would peel her open.
The sterile scent of his own release still hung in the observation room air, a sour counterpoint to the antiseptic chill. Humphrey blinked, the afterimage of Bree’s climax seared onto his retinas, the echo of her scream – his name – a raw vibration in his bones. He needed to refocus. Olsen. He needed Olsen’s failure.
With sharp, efficient movements, he cleared the screens showing Bree, her violated ecstasy banished. His fingers flew over the console, pulling up Subject Olsen’s file, the digital folders stark and impersonal. He selected Session 1. The feed flickered: Mark Olsen, bravado still in tact, hopeful, strapped supine to the platform, the machine’s articulated arm poised near his groin. This was the successful one. Humphrey remembered – the machine’s smooth, lubricated sleeve had descended, enveloping Olsen’s flaccid cock with a soft, wet sound. Gentle suction engaged, subtle vibrations thrumming. Olsen gasped, his hips lifting slightly off the platform as the machine began a slow, relentless stroking rhythm, its grip perfectly calibrated. "Oh... oh wow," Mark breathed on the audio, his eyes fluttering shut, a sheen of sweat already appearing on his forehead. The machine worked him steadily, the synthetic sleeve sliding up and down his thickening shaft with obscene slickness, twisting slightly on the upstroke, mimicking expert fingers. Olsen’s breath hitched, became ragged pants. "Fuck... yes... like that..." His body tensed, back arching, a guttural groan tearing from his throat as thick ropes of cum spurted violently into the machine’s receptacle. Successful modulation. Pleasure delivered. Contained. Controlled.
Humphrey tapped the console, the feed jumping to Session 2. The failure. Olsen was prone now, restrained tightly, face pressed into the headrest, his ass exposed. The machine’s thick polymer shaft, slick with lube, pressed against his clenched hole. Olsen’s muscles visibly trembled. "Easy... easy now," he muttered, voice tight. The shaft pressed harder, an inexorable pressure. "Shit... wait, it’s too—" The machine pistoned forward, a brutal, deep thrust burying the shaft in one savage movement. The machine, oblivious, began its programmed rhythm – a deep, slow withdrawal followed by another brutal, plunging thrust.
The inevitable moment when Olsen screamed, a raw, animal sound of pure terror and agony, his body bucking wildly against the restraints. "GET IT OUT! GET IT FUCKING OUT OF ME!" he shrieked, his face contorted, eyes wide with primal panic. Watching now, Humphrey could see the conflict and confusion on Olsen’s face plain as day. His body was at war with itself, wanting to flee and lean in all at once. "NO! STOP! PLEASE! IT HURTS! IT’S RIPPING ME APART!" Olsen sobbed, drool slicking the platform beneath his mouth, his body a rigid arch of agony and shameful ecstasy rolled into one highly combustible scenario.
The proprioceptive feedback loop had catastrophically failed to understand the nuance of what was warring inside Mark. Pain commingled with pleasure, pure and unmodulated, the discovery of being dominated past his own natural boundaries and enjoying it, had triggered a panic cascade the machine couldn’t override. Humphrey watched, his expression impassive but his mind racing, comparing Olsen’s raw, unadulterated anger to Bree’s agonized ecstasy under his hand.
The variable was glaringly obvious. Olsen lacked the crucial counterpoint. Yes, the manual stimulus had been necessary for the achievement of the physical climax, but it was the absolute acceptance of her own desires that made the difference between her success and Mark’s failure. She understood what the machine was doing to her, and she wanted it to. The targeted pleasure of his hand to transform the violation was a required variable, but one she constructed herself.
He leaned back, the cold metal of the chair pressing against his spine. Olsen’s panicked screams faded from the speakers, leaving only the low hum of the lab. Bree had to administer the stimulus. Her proven sensitivity, her demonstrated capacity to channel intensity into control, was essential. Olsen needed that precise touch, that level of control and direction, pulling him towards release even as the machine tore his defenses apart. He wouldn't break this time. He’d be more receptive.
In the observation booth, Humphrey watched the twin monitors intently. On the left, Bree’s recorded anal session played: the moment the machine’s brutal thrusts intensified, her body locking, her mouth open in a silent scream of ecstatic surrender as Humphrey’s hand worked her clit. On the right, the other feed: Mark’s face contorted in agony and confusion, his body rigidly resisting the deep penetration, even as his hand jerked towards his thickening cock roughly. The machine pushed harder, deeper, the servos whining with strain. Humphrey saw it simultaneously on both screens: the precise moment the machine crossed the threshold from stimulation into violation. Bree, on the recording, arched into the brutal thrust, her hips lifting, welcoming the tearing depth, her surrender absolute. Mark, confused, instinctively tried to clench, to pull away, his muscles fighting the invasion despite the slickness and the cock hardening in clear view. "Resistance," Humphrey murmured, his eyes flicking between the screens, captivated by the stark divergence. "She yields. He fights." Bree’s recorded gasp of "Fuck YES!" filled the booth, perfectly timed with Mark’s live, choked whimper of "Too much…". The variable wasn't just the hand. It was the mind. The surrender. Olsen lacked it. Bree possessed it instinctively.
The observation booth hummed with low electric vibration, the sound of data streaming, of flesh reduced to numbers. Humphrey stood rigid before the twin monitors, the blue light cutting across his face, sharpening every line of concentration into something almost predatory.
On the left, Bree’s recorded session unfolded in merciless high-definition. Her body was a map of surrender—each breath, each tremor catalogued, time-stamped, measurable. The machine’s thrusts grew savage, relentless, yet she didn’t recoil; she rose to meet them. Her back arched like a bow drawn to breaking, her mouth open, her face slack with bliss. Her voice, ragged and unrestrained, bled through the booth speakers—“Fuhhh—uck—YES—!”
On the right screen, Mark Olsen’s live feed twitched and stuttered. His body strained against the apparatus, cords of muscle trembling in futile resistance. His face was twisted—confusion, pain, pride all warring at once. The machine’s pistons hissed as they drove deeper, the servos whining, the mechanical rhythm slipping toward something frantic. “Too much—” Mark gasped, the words bitten off between clenched teeth as his body jerked in half-suppressed revolt.
Humphrey watched the two images simultaneously, side by side—the yielding and the resistance, the open and the clenched, the woman whose pleasure had overtaken the machine’s purpose and the man now trying to assert dominance against it. He murmured to himself, eyes flicking from screen to screen, voice low and analytical but with something darker threading through: “Resistance… she yields. He fights.”
The booth filled with the obscene symphony of their juxtaposition—Bree’s recorded moans syncing uncannily with Mark’s live gasps. When she cried out “Yes,” he grunted “No,” when her body lifted, his recoiled.
“The variable,” Humphrey whispered, “isn’t mechanical.” He leaned closer, his reflection ghosting between the two screens. “It’s cognitive. It’s psychological. The threshold isn’t purely physiological. It’s… surrender.”
He pressed the intercom button, recording a voice memo into the system. “Observation, cycle sixteen. Correlation emerging between subject predisposition and machine synchronization. Female subject Bree exhibits superior adaptation and neural harmony—suggesting internal factors beyond physical calibration. Possible predisposition toward yielding response pathways. Male subject Olsen demonstrates counterproductive resistance behaviors—manifested in increased muscular tension and conflicting neural patterning. Further examination required.”
He ended the recording, jaw tight, pulse ticking in his throat. The hypothesis felt too alive beneath his skin, humming like voltage. He opened another console window, calling up the intake archive—Bree’s and Mark’s preliminary interviews.
Mark’s video filled the left monitor. The man lounged in his chair, cocky grin in place, sleeves rolled up, voice easy. “I’m pretty open-minded,” he said, smirking straight at the camera. “I can handle anything. You’ll see.” His posture screamed control—shoulders loose, eyes gleaming with self-certainty. “I’m not shy about sex, if that’s what you’re asking. I know what I like, and I like a lot.” He laughed, leaning back, the movement almost rehearsed.
Humphrey fast-forwarded through the banal confidence, through the bravado and the smirks, watching the way Mark’s mouth always curved upward, the performative charm. “Confidence,” Humphrey muttered into another memo. “Excess self-assurance. High dominance display. Low adaptive pliancy. Potential correlation to mechanical resistance. Subject assumes control inherently, rejects imposed rhythm.”
He switched feeds.
Bree appeared—nervous, small, fingers clasped tightly in her lap. Her hair was different then, shorter, unkempt, the shadows under her eyes soft with fatigue. “Um… I’m doing this because I need the money,” she’d said, barely above a whisper. “I’m not really… experienced. I’ve only been with two partners. I mean—sexually.” Her voice trembled; she looked down, avoiding the interviewer’s gaze. When asked about physical sensitivity, she blushed hard, stammering through the words “pretty sensitive… I guess too sensitive sometimes.”
Humphrey leaned closer to the screen, transfixed.
There she was—timid, fragile, trying to fold herself into invisibility. The same woman whose recorded image, just hours earlier, had screamed herself raw as her body broke open under the machine. The contrast was staggering, erotic in its purity.
He reached absently for the intercom again, voice thickening despite himself. “Subject Bree displays high initial inhibition, submissive affect, financial motivation overriding discomfort. Subsequent exposure yielded total adaptive surrender. Transition from restraint to receptivity complete. Predisposition indicators: latent compliance, high empathic responsiveness, emotional contagion potential—”
He paused, breath audible through the mic.
His eyes stayed fixed on her frozen interview frame—her downcast eyes, her bitten lip, the uncertain flicker of vulnerability. Then, without meaning to, his gaze flicked back to the other monitor—the one where her body had taken the machine’s brutal rhythm and made it hers.
He swallowed. The air in the booth had gone thick.
“Dr. Park,” he murmured to no one, to the ghost of her warning. “You were right to worry.”
He sank back into the chair, eyes heavy with fascination and something more dangerous. He should’ve stopped. He should’ve closed the files, logged the findings, written the report. But he couldn’t. He queued both videos again—Bree’s interview and Bree’s session—side by side this time. Innocence and debasement, bookended by science.
He pressed play.
On one side, the woman on camera fumbled through her words, cheeks pink. “I’m not sure what to expect.”
On the other, the same woman’s voice broke into gasps, animal, ecstatic: “Yes—oh god—yes!”
The contrast hit him like heat, crawling up his neck, sinking into his spine. He felt it—her transformation wasn’t just data. It was evolution. A mind unlocking itself under the right stimulus.
He forced himself to speak again, voice rougher now, the recording catching the rasp. “Observation: possible psychosexual correlation between submissive disposition and optimal machine synchronization. The machine may respond better to surrender than to dominance. Further trials required to confirm…”
His hand hovered over the stop button. He didn’t press it.
Instead, he rewound Bree’s session five seconds—just enough to hear the sound of her cry again. The pitch, the way it cracked from pain into pleasure. The way she yielded.
He sat there, watching her writhe, watching the measured lines of his own composure begin to blur.
Somewhere deep inside, the boundary of research dissolved—quietly, irrevocably.
And Dr. Humphrey, the man who built the protocol to conquer human unpredictability, realized he was no longer observing.
He was wanting.