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It’s spring break, a completely average day in a suburban house, empty except for two boys. Robbie is sitting on his bed next to his older stepbrother. The two are having a conversation about life, drifting between subjects; Aaron has moved out of the house and into a college dorm, so they don't see each other much.
“How's Maria?” Robbie asks, inquiring about Aaron's girlfriend. He remembers her being a small, mousy sort of girl. “We broke up,” Aaron says. He seems down, but not wrecked by it. Robbie asks him why.
“I was too big. Like, my dick.”
“Oh.” Robbie is slightly taken aback at his candor, but can't help but be intrigued. “Um... how big is it?”
Aaron shrugs nonchalantly, as if discussing the weather. “About eleven inches hard. She just couldn't handle that.” He looks over at Robbie, studying his face for reaction. Part of him wonders if Robbie would be intimidated, or perhaps even turned on by such a size. “You ever wondered what I'm packing under these jeans, little bro?” Aaron teases, a mischievous glint in his eye. “I bet you're curious…”
Robbie punches him lightly in the arm, trying to hide his interest. “C'mon man, that's fucked up. Like, how many girls can’t handle it?”
Aaron chuckles, leaning back against the wall. “Enough to make me realize most women aren't equipped to deal with a cock like mine. But hey, I've got no regrets. It's who I am.” His gaze drifts back to Robbie, eyes lingering on his slender frame. “Speaking of bods though... yours must be pretty impressive for a kid your age. Ever jerk off in front of a mirror?” Aaron's tone is playful, but there's an underlying current of genuine curiosity. He's long been fascinated by his young stepbrother's developing sexuality.
“Pfft... impressive, sure,” Robbie snorts sarcastically. Aaron's father got together with Robbie's mother a number of years ago, well before Robbie transitioned to male. Aaron's been watching it happen, but since he moved out, Robbie has gone through some real development; he's gotten hairier, more muscular, voice deeper. At 16, he fits the part of a teenage boy well into puberty.
Aaron nods approvingly. “Yeah, you've definitely filled out nicely since I left. I remember when you were still playing with dolls…” He grins, remembering Robbie's former femininity fondly despite his stepbrother’s embarrassment. “But seriously, have you seen yourself naked lately? What do you look like down there now?” Aaron's curiosity is piqued, wondering if Robbie's transformation extends to his genitals as well. He's always been drawn to smaller forms, and the thought of seeing his young stepbrother's is both thrilling and taboo.
Robbie shifts nervously. “Well, uh, my clit got pretty big from hormone therapy... It's, like, 2 inches hard. Which is pretty big for a trans guy,” he says, a bit proudly.
Aaron's eyes widen slightly at the mention of Robbie's enlarged clitoris, finding himself strangely aroused by the idea. “Damn, that's impressive. I didn't realize hormone therapy could do that.” He leans in closer to Robbie's side on the bed, lowering his voice conspiratorially. “You know, I've always wondered what it'd feel like to touch a dick like that. So sensitive and all…” Aaron reaches out tentatively in a rush of boldness empowered by arousal, his hand nearing Robbie's groin as if preparing to make contact. “Mind if I take a peek, little bro? Just to satisfy my curiosity.”
Silently, Robbie nods. When Aaron's large hand lightly cups Robbie's mound through his pants, the younger boy shudders. His clit, already hard from the heated conversation, twitches palpably.
Feeling Robbie's twitching erection through his jeans, Aaron smirks to himself. He gives Robbie's crotch a gentle squeeze, fingers splaying wide to encompass the mound. “Feels like you're getting excited, bro,” Aaron murmurs, his thumb rubbing circles over the sensitive area through fabric. “This is one hell of a dick.” With deliberate slowness, Aaron unzips Robbie's fly and slips a hand inside his briefs. His palm makes direct contact with Robbie's stiff, engorged clit, pressing into it firmly. “Fuck, you're really packing heat here,” Aaron breathes, marveling at the texture and temperature of Robbie's arousal. “Bet this thing throbs when you cum…”
Robbie flushes deeply, but his own curiosity matches Aaron’s. “I wanna see yours too,” he says. “I never saw a guy's dick before in real life.”
Aaron chuckles, pleased by Robbie's boldness. “Alright then, let's give each other a show.” He stands up and starts unbuckling his belt, popping the button on his jeans and slowly lowering the zipper. With a smirk, Aaron tugs his denim down, along with his boxers, revealing his massive, semi-erect cock. It juts out proudly, thick veins snaking along its length, the tip already glistening with precum. “There he is, kiddo,” Aaron says, giving his shaft a slow stroke. “Eleven inches of pure, uncut meat. Not bad for a college boy, huh?” He steps closer to Robbie, his heavy balls swinging with each movement. Aaron positions himself between Robbie's legs, looming over his younger sibling.
“Fuck…” Robbie whispers, lips parted. The huge thing is pointing right at him, wafting musk. Robbie's cunt throbs and leaks a drop of slick into his boxers.
Noticing Robbie's reaction, Aaron grins wickedly. “Like what you see, bro?” He takes hold of his thick cock and begins pumping it slowly, the wet sound of skin on skin filling the room. Precum dribbles faster, slicking his shaft. “Tell you what, why don't we have a little fun? I'll jack off while you play with yourself, and maybe we can swap techniques.” Aaron's eyes gleam with fascination as he watches Robbie's hands fumble with his own pants, eager to see the young trans man explore himself.
Robbie quickly pulls off his pants and underwear and lays down on his bed. His hand reaches down to rub two fingers over his erect, fat clit; the contact makes his back arch. He's keenly aware of Aaron's rapt attention and the massive pole looming inches away.
Aaron licks his lips as he watches Robbie touch himself, mesmerized by the sight of his stepbrother's hardened clit glistening with arousal. “Oh fuck yeah, just like that,” he encourages, his voice husky with desire. “Show me how you like to play with it.” Aaron resumes stroking his own thick shaft, precum easing the motion. He leans in closer as he continues to pump himself. “You know, I've always fantasized about a cock like yours,” Aaron admits, his eyes darkening with lust.
“Me too…” Robbie breathes. Aaron sits and swings his legs sideways over the bed, and now he's kneeling between Robbie's thighs, leaning over him. Robbie swallows thickly.
Aaron guides his heavy cock to hover just above Robbie's slick, throbbing clit, letting the head graze against it teasingly. “Mmm, so warm and wet already,” Aaron groans, his hips rolling gently to rub his cock head against Robbie's sensitive nub. “Wanna bury myself deep in this tight cunt.” He leans down and captures Robbie's mouth in a rough kiss, tongue delving past his lips to taste every inch. His free hand grips Robbie's hip possessively as he continues to tease his cock against Robbie's slit, building friction and making him squirm.
“Feels... ah! It's so warm…” Robbie moans between meetings of their lips. His hips rut against Aaron's, frotting his cock against his t-dick. Slick from his cunt spreads hot and wet over Aaron's shaft as he slides it between his lips. The feeling of being utterly dwarfed by his stepbrother’s mass makes Robbie lightheaded.
Aaron breaks the kiss to pant heavily, his face flushed with arousal. “Goddamn, you're soaked for me already, huh?” He rocks his hips harder, sliding his thick cock through Robbie's slick folds, coating himself in the young trans man's arousal. Aaron's own precum drips steadily, mixing with Robbie's juices to create a slippery glide. “I'm gonna make you cum so hard, little bro,” Aaron growls, his voice ragged with need. “Gonna fill this tight cunt with my seed until you're dripping with it.” With that promise, Aaron lines up his glans with Robbie's entrance and pushes in, breaching that first delicious ring of resistance.
“Argh...!” Robbie hisses through clenched teeth, back arching and cunt squeezing tight around Aaron's fat cock head. “Please go slow,” he pleads, knowing his shaft only gets thicker, but there's no turning back now; he's already been broken open.
Aaron pauses, feeling Robbie's tight heat enveloping just the tip of his cock. He grits his teeth, fighting the urge to thrust deep and claim his stepbrother fully. “Easy, I gotcha,” he reassures, though his voice quavers with restraint. “Just relax and let me take care of you.” Slowly, deliberately, Aaron sinks another inch into Robbie's clenching passage, giving him time to adjust to the size. He waits for Robbie's response, watching for signs of discomfort to ease before pushing in further. “That's it, nice and easy,” Aaron coaxes, his breath hot against Robbie's ear. “You were made for this, little bro.”
Robbie whines deep in his throat. He didn't tell Aaron that he was a virgin, only having made out with classmates behind his high school; now he's taking a cock nearly as thick as a coke can and longer than two stacked up. Something feels like it's ripping apart, and it's not his hymen. He looks up at Aaron as he looms over him, obscuring Robbie's far smaller body. Aaron's eyes are shut with bliss.
As Robbie's walls stretch to accommodate his girth, Aaron's eyes snap open, meeting his stepbrother's gaze with a look of primal satisfaction. He's barely inside with half of his length, yet the young trans man's resistance is melting away under the onslaught of sensation. “Fucking hell, you feel incredible,” Aaron groans, his voice thick with lust. “So tight and hot, like you were made for my cock.” With a guttural grunt, Aaron surges forward, driving the rest of his impressive length into Robbie's incredible heat. He fills the boy to the brim, his heavy balls slapping against Robbie's ass as he claims his cunt in one powerful thrust. “Take it!” Aaron commands, his hips stopping abruptly as he tries not to blow his load right there.
“It hurts…” Robbie says, eyes distant and blurry with tears, yet his clit pulses with every graze against it. His stepbrother's length is pushing his cervix upwards, blood is dripping down the crease of his thigh, but Aaron shows no sign of stopping. Every throb of his massive cock pushes Robbie's walls apart even further.
Aaron's grip on Robbie's hips tightens as he starts to move, each thrust sending waves of pleasure coursing through his veins. The sound of flesh slapping against flesh echoes in the room, punctuated by Robbie's cries. “Shh, just let it happen,” Aaron murmurs, his voice low and soothing despite the intensity of his movements. “Your body was made for this, to take a cock deep inside.” He picks up the pace, fucking into Robbie with long strokes that send the boy's world spinning. Aaron's eyes roll back in ecstasy as he savors the feeling of Robbie's inner walls gripping him like a vice. “Gonna fill you up so good, little bro,” Aaron promises, his thrusts growing more erratic as he nears his climax.
Robbie screams, body jerked by every brutal thrust. The fat head of Aaron's cock is softening his cervix like a battering ram. Aaron's thrusts become almost violent as he chases his release, driven by a primal urge to claim every inch of Robbie's body.
With a final, savage push, he buries himself to the hilt, his swollen cock head kissing Robbie's womb. “Yes, take it all, you little slut!” Aaron snarls, his voice raw.
Robbie screams. His cervix is utterly crushed by his stepbrother's cock, but Robbie is cumming through the pain. As Robbie's orgasm overtakes him, with a guttural roar, Aaron erupts, his thick seed flooding Robbie's abused channel in powerful spurts. His bulbous cock head becomes lodged inside, continuously spurting thick cum into his little brother's cunt. Each pulse of his cock sends another load of hot, sticky semen deep into Robbie, soiling his cunt.
Aaron's thrusts slow to slow pumps, milking every last drop of cum from his spent cock. He remains buried deep inside his stepbrother, savoring the feeling of Robbie's inner walls fluttering around him as they both ride out the aftershocks of their intense coupling. “Mmm, that's it, little bro,” Aaron purrs, nuzzling Robbie's damp neck, wet with sweat and tears. After some time, Aaron carefully withdraws his softened cock from Robbie's broken hole, a river of combined cum trickling out to stain the sheets beneath them. He pulls Robbie into a tender embrace, cradling the young trans man against his chest as they lay in the aftermath of their coupling.
Robbie lies limp in his arms, drained. Semen mixed with bright streaks of blood seeps onto the bedsheets between them. As he remains motionless in his brother’s embrace, Aaron's mind begins to whirl with thoughts of their illicit encounter. A part of him is thrilled by the knowledge that he's claimed his stepbrother, marked him as his own in the most intimate way possible.
“Wait,” Aaron murmurs, a sudden realization dawning on him. “Robs, are you...?” Aaron trails off, his eyes widening as the implications sink in. He gently tilts Robbie's chin up, studying his face with a mix of concern and sick excitement. “You weren't on anything, right? No birth control?” Aaron asks, his voice tinged with a hint of panic. “Because if we just... you know…”
“I'm sure it'll be fine…” Robbie mutters, his stomach sinking. He's on testosterone, he hasn’t had a period in months. Surely nothing will happen… Right?