Chapter 10: Experiment
Brenda’s ragged breathing finally steadied against his chest, but her fingers remained pressed deep into the tight space between the bases of his cocks. Harold felt it too—a dense, unnatural heat radiating from his pelvis, a low thrum more felt than heard beneath his skin. Both shafts remained buried deep within her, rigid and unyielding, a persistent, swollen weight inside her stretched channel.
"Still rock fucking hard," she whispered, her voice scraped raw. Her fingertip traced the thickened root of the smaller cock, probing where it seemed to anchor deeper into his pubic bone than before. "And this root… Harold, it feels… it’s digging in. Like it’s setting up fucking shop."
A cold thread of fear pierced Harold’s exhaustion. "It’s not normal, Bren. This can’t… staying like this for hours? Growing? It feels… wrong." He shifted minutely, causing her to gasp as the dual columns moved inside her sensitive flesh. "Like something’s out of control."
"Fuck normal," she hissed, lifting her head. Her eyes were dilated, blazing with a fervor that eclipsed any trace of fatigue. She pushed herself up slightly, wincing at the soreness radiating from her core, a deep ache mingled with persistent, demanding heat. "Look what it did to me. Look what I took." Her hand slid down her belly, fingers slipping through the slick mess of sweat and their combined release coating her thighs. She touched the swollen, stretched rim of her entrance where both cocks still disappeared into her. "Feels… ruined. And I fucking crave it being ruined again. Right now."
She locked eyes with him, her gaze unwavering, predatory. "Another pill, Harold."
His stomach clenched. "Jesus, no! Look what one did! We don’t even know what these are! This… sensation… it’s not just arousal. It feels… invasive."
"Please, baby," she begged, her voice dropping to a husky whisper loaded with need. Her hand slid from her cunt back to his groin, her fingers wrapping possessively around both shafts, squeezing. Harold groaned, his hips bucking helplessly against her grip. "Just one more. I need to see how big they get. How thick that little one swells. How deep it plants itself inside me next time." She leaned down, her lips brushing his ear. "Imagine it. Filling me until I scream. Stuffing me so full you feel both heads kissing my fucking cervix."
Her words, her touch, the relentless pressure inside him – they ignited a fresh wave of desperate, terrifying lust. The fear warred with the insistent thrumming in his groin. "Brenda…"
"Please, Hal." Her tongue flicked his earlobe. "For me. To see how far this goes." Her hand tightened, pumping both cocks slowly, deliberately. Precum leaked anew from both tips. "I’m still so fucking wet for you. Still aching to be stretched wider. Help me find out."
He closed his eyes. The humming intensified. The promise of more, of her broken cries, of that impossible fullness… it drowned the caution. "Christ, okay," he breathed, the words thick with dread and anticipation. "Just one more."
"Good boy." She kissed him fiercely, a clash of teeth and tongues, then pushed herself off him with a sharp gasp as both shafts pulled free. His cocks stood proud, gleaming slickly in the dim hallway light, the smaller one visibly thicker at the base than it had been minutes before. Brenda scrambled to her feet, her movements stiff but determined, and hurried towards the bedroom.
Harold lay on the floor, staring at the ceiling, the cool air a shock on his heated skin. The hum in his groin felt like a gathering storm. He heard the rattle of the small pill bottle from the bedside table, the hum of the refrigerator suddenly loud in the quiet apartment.
Brenda returned, holding the bottle and a glass of water. She knelt beside him, shaking out a single, unassuming white tablet. "Here." Her voice was steady, her eyes fixed on his twin erections. "Swallow it."
His hand trembled as he took the pill. He hesitated, staring at it. "What if…"
"Now, Harold," she commanded, pressing the glass into his other hand.
He tossed it into his mouth and gulped down the water. It felt like swallowing a stone. Dread coiled in his gut, intertwined with a sharp spike of illicit excitement.
"Now what?" he whispered, setting the glass aside.
"Now we wait," Brenda murmured, her gaze raking over his rigid cocks. She licked her lips. "And while we wait… I want both of them in my mouth." She pushed at his shoulder. "Bed. Now."
They stumbled into the small bedroom, the air thick with the faint scent of lavender from the sheets and the lingering musk of their previous encounter. Harold fell back onto the worn mattress, springs groaning. Brenda didn’t hesitate. She climbed over him, the muscles in her thighs flexing, and positioned herself so her glistening, swollen cunt hovered directly over his face. Her bright red hair cascaded down around her hips. "Eat me, Hal," she ordered, lowering herself onto his mouth. "Get me dripping."
The musky, heady scent of her arousal filled his nostrils. He didn’t need prompting. His tongue plunged into her wet heat, lapping at her slick folds, finding her engorged clit. She cried out, grinding down hard against his mouth. "YES! JUST LIKE THAT! FUCK MY FACE WITH YOUR TONGUE!"
Her hands went to his groin. One closed firmly around his main shaft, squeezing the thick, familiar girth. The other encircled the smaller cock, her fingers barely meeting around its thickened base. She began stroking them both, her movements urgent, possessive. Then she bent forward, her mouth descending on the larger cock. She engulfed the head, sucking hard, her cheeks hollowing.
Harold moaned against her pussy, his tongue driving deep. The dual sensations were overwhelming: the wet, clenching heat of her cunt on his face, the fierce suction on his main shaft, the tight, rhythmic friction of her hand pumping the smaller one. He focused on her taste, the salt and musk, the way her inner muscles fluttered against his probing tongue as he flicked her clit. "You taste… fucking divine," he mumbled into her folds.
She released his cock head with a wet pop, gasping for air, a string of saliva connecting her lips to the glistening tip. "Eat my fucking pussy like you mean it, Hal," she commanded hoarsely, her hand still working his smaller shaft furiously. "Get it soaking for that monster cock… and its hungry little brother." She bent her head again, taking the main shaft deeper this time, her throat working to accommodate its thickness.
He doubled his efforts, lashing her clit with the flat of his tongue, then spearing her opening with stiffened thrusts. Her juices flowed freely, coating his chin. Her hips rocked frantically against his mouth. "OH GOD! YES! MAKE ME CUM ON YOUR TONGUE! MAKE ME—"
Her words dissolved into a high-pitched whine as her body tensed. Harold felt her cunt clench rhythmically around his tongue, a warm gush flooding his mouth. He drank her down, his own arousal spiking violently. The stimulation from her mouth on his main cock and her hand on the smaller one was relentless. He felt the pressure building, a familiar tension coiling low in his belly.
But it felt… lopsided. The overwhelming need centered on his main shaft. "Brenda… I'm… close…" he gasped, pulling back slightly from her throbbing cunt.
She sucked harder, bobbing her head, her hand squeezing and stroking the smaller cock with equal intensity. "Cum in my mouth, baby," she slurred around his length. "Give it to me."
The orgasm hit him like a surge of electricity, but it only came from one source. His main cock pulsed violently, thick jets of hot cum erupting deep into her waiting mouth. "FUCK! BRENDA, I'M—" He arched his back, his cry strangled as he emptied himself down her throat.
She sucked fiercely, swallowing convulsively, milking every spurt. "Mmm… fuck yes… good boy," she moaned as the last pulses subsided. She lifted her head, lips slick and swollen, a trickle of white escaping the corner of her mouth which she quickly licked away. Her hand never stopped pumping the smaller cock. It remained iron-hard, throbbing visibly in her grip, untouched by his climax.
Harold panted, the intense release from his main shaft leaving him momentarily dazed. But the smaller cock… it burned. It throbbed with an insistent, unmet ache. He could feel its desperate, separate need.
Brenda stared down at it, her eyes wide with disbelief and raw fascination. Her fingers tightened around its rigid length, feeling its heat, the distinct pulse beneath the skin. "Holy… shit… Hal…" she breathed. Her thumb rubbed over the weeping slit. No cum emerged. Just a bead of clear precum. "It didn't come." She looked from the cock to his face, her expression awestruck.
As she watched, the smaller cock seemed to swell further in her hand. The veins stood out more prominently, snaking along its thickened shaft. A subtle, visible ripple ran along its length, like thick muscle flexing beneath taut skin. It pulsed heavily, growing denser, harder. "Look at it," she whispered, her voice trembling with excitement. "It’s fucking growing. Right now. Thickening. Getting meaner." Her grip became almost reverent. "It’s still starving, baby. Still fucking starving for my cunt."
Brenda’s fingers tightened, feeling the dense heat of it pulsing against her palm. It wasn’t just rigid; it was changing. A visible ripple traveled beneath the stretched skin, thickening the shaft like hardening clay. Precum beaded furiously at the slit, thick and clear, as it strained against her grip.
"Jesus, Hal, feel it," she gasped, her voice shaking. Her other hand squeezed his main shaft reflexively, slick from her own wetness dripping onto his chin. "It’s… swelling. Right fucking now. Getting thicker. Meaner." She watched, mesmerized, as the angry red head seemed to darken, engorged veins standing out like cords beneath the surface. "Fuck, it’s hungry."
Harold groaned, a sound of overwhelmed sensation. The burning thrum deep in his groin intensified, centering on the base of the swelling cock. He felt it stretching him internally, a deep ache that was both agony and a terrifying, consuming need. "Bren… it burns… feels like it's… rooting deeper…"
"Let it," she breathed, her hips grinding involuntarily against his chin, smearing slick arousal over his jaw. Her eyes were locked on the transformation in her hand. The smaller cock was rapidly losing its label. It thickened perceptibly, the girth in her fist increasing second by second, the angry head flaring wider. "Look at it grow, baby. Look what it wants to do to me." Her free hand slid down her belly, fingers plunging into her own soaked cunt, spreading her lips. "Wants to ruin this. Split me wide. Stuff me full alongside its big brother."
She pumped it slowly, deliberately, feeling the dense resistance, the heat searing her palm. It was easily five inches now, maybe more, the ridge of its head pronounced and demanding. The distinct veins pulsed aggressively. "God, it’s almost… almost as big as the other…" The main cock twitched violently in her other hand, reacting to her words, her touch, the sight of its twin surging towards equality. Harold gasped, arching his back off the mattress, the dual stimulation overwhelming.
Suddenly, with no warning, his main cock convulsed. Thick, hot ropes of cum erupted violently from its tip, splattering Brenda’s chin and neck. "FUCK!" Harold cried out, hips jerking. "SHIT! BRENDA!" The orgasm ripped through him, focused solely on the main shaft, while the other remained an iron-hard, throbbing pillar of unmet need in her fist.
Brenda flinched at the sudden warmth on her skin but held fast. She watched the main cock spasm, painting her, but her gaze snapped back to the twin in her hand. It pulsed even harder, visibly swelling another fraction as the main shaft emptied itself. Its color deepened, the network of veins stark and raised against the heated flesh. It hadn't softened a micron. It looked brutal. Primordial.
She released the main shaft, still dribbling cum, and brought both hands to the transformed cock. Her fingers couldn't meet around its new, substantial girth. She stared, her breath catching. The thing in her hands was no longer smaller. It was thick, veined, angry, and absolutely erect. A perfect, terrifying twin. "Oh… fuck me," she whispered, her voice thick with awe and raw desire. Her cunt clenched around her own fingers, dripping freely onto Harold’s chest. "Hal… it’s not the smaller cock anymore."