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Neither of them remembers how this all started. Most likely, Ratio surmises, the seed of curiosity was planted ever since his dear student aboard the Astral Express described in detail that fateful battle with Aventurine of Stratagems. The newest member of the Nameless isn’t immune to exaggeration when it comes to recounting their dramatic escapades, of course, but Ratio must admit that the idea of facing off Aventurine in this allegedly more powerful form has piqued his genuine interest, in multiple ways.
Which is a rather long-winded way of explaining why he’s currently spread in his bathroom, three digits deep into his own ass while sticky lubricant trickles down his thighs. He curls his fingers around that familiar spot, lets the wet heat envelop his hand and stifles a groan. He’s repeatedly made clear to Aventurine that, yes, he’s strong enough to take it, he remembers their safeword(“Ducky”), he’s not so easily intimidated, and - he simply wants Aventurine. All of him. The gambler finally shuts up after that, his pupils wide with surprise, and then desire.
So here they are. He feels the ring of muscle clench hungrily around nothing, his glistening fingers being nowhere near the usual girth he’s accustomed to. Ratio is impatient for once, and pulls on his bathrobe. His flushed face looks back at him in the mirror and he swallows, heat coiling deep and low between his legs.
He steps out to where Aventurine is waiting. There he is in all his glory, and Ratio’s breath catches.
His student certainly did not exaggerate how impressive Aventurine is like this. Sheer power radiates from the one who is blessed with a piece of the Amber Lord, his entire being coated in an aura of brilliance. Ratio walks closer in awe, finally registering just how big Aventurine is in this form. The Stoneheart easily towers over him, nearly twice his size, and despite his own strength Ratio has no doubt that Aventurine can snap him in half if he wanted. He gulps when he realizes how that fact doesn’t deter him in the slightest.
Aventurine watches him almost motionlessly. No, “watch” isn't the right word, as the smooth mask over his face obscures all thought and betrays no expression. More precisely, Aventurine is covered entirely from head to toe, draped in layers of fabric even more extravagant than his usual attire. Not an inch of skin shows, and Ratio shivers from awareness of his own nakedness, his bathrobe now haphazardly discarded at his feet.
Still Aventurine makes no move, as if waiting for Ratio to call an end to all of this. Ratio pays him no mind, and directs his gaze towards the luminous chestpiece covering his torso. He tips his toes and traces its shape carefully, letting his fingers roam over the sleek surface, then draws them further down in slow circles. He’s about to note the strangely velvety texture of the suit when Aventurine catches his wrist, and Ratio is drawn to his hands - are those claws? Talons? He closes his palm over one digit and feels its sharpness, definitely lethal enough to cut skin.
“Fascinating,” he murmurs, and Aventurine’s breathing thickens. Ratio guides him towards the bed before kneeling and finally reaching for his crotch; a quite conspicuous bulge has formed during his fondling earlier, and Ratio is eager to release his object of interest from its confines.
In all honesty, this whole affair of harnessing the power of a cornerstone is a scientific wonder in itself, and Ratio is curious about its mechanisms, truly. But if the transformation comes with other benefits, the scholar would be remiss to not take full advantage of them. Aventurine’s cock twitches in his hand, and already he can barely wrap his fingers around its girth. He strokes from base to tip, once, twice, taking in the monstrous length that is about to enter him. His own cock hangs heavy between his legs, the sticky wetness around his hole making him squirm.
Aventurine’s hands move to frame his face, careful not to pinch his skin. Ratio gives a tentative lick, letting the musky bitterness wash over his tongue. The taste is slightly different than usual, he muses, then laps at the tip until the engorged shaft fully hardens in his mouth. He swirls his tongue diligently, mapping every inch of Aventurine’s swollen, flushed cock, and savors how the thick veins pulse under his thorough efforts.
Aventurine’s legs tense, and Ratio is pulled closer. He breathes in deep, inches lower to hollow his cheeks and suck properly, or at least tries to - the massive length invariably makes him choke, and Aventurine shudders when his spasming throat tightens. Precum and saliva pool under his chin and drip onto his heaving chest, but now’s no time to play the prim and proper scholar; Ratio gives a muffled moan from being just so full, well aware what the image of his face stuffed with cock does to the man above him.
Gently, he guides Aventurine’s hands to the side of his face and lets his jaw fall slack. The mask remains inscrutable as Aventurine begins to fuck his throat, and Ratio closes his eyes - can only hold still as the thick shaft pistons into him. He’s so hard it hurts, the fantasy of silent danger stirring arousal in a way he never expected. He hastily plunges his fingers into himself, reaching for the spot that draws out a string of whimpers; the sticky wetness from before drips and splatters onto the floor, and Ratio knows his now tear-stained, drooling mess of a face spurs Aventurine on like nothing else.
He braces against Aventurine’s quickening pace, doing his best to gulp in air whenever possible amidst sounds of himself gasping and choking. And then it happens - Aventurine holds him in place against his crotch, and Ratio feels his mouth widen against the base of his cock. For a few seconds, he’s really quite in awe of himself, until spots begin to flicker in his vision, and his chest feels as if it’s about to burst - from lack of air or the image of Aventurine using his throat as just another hole, he doesn’t know.
Then Aventurine groans above him, and suddenly the tightness is gone and Ratio can breathe again. He gasps, drinks in the air greedily, and flicks his abused tongue around his lips. Aventurine waits for him patiently, his glistening cock a sticky, quivering mess.
It’s been long enough. Ratio climbs shakily onto the bed, lies on his back and tugs Aventurine with the back of his foot. The Stoneheart looms over him, his long, cold fingers moving to grasp tightly onto his waist. Ratio locks his legs behind him, gives him what he hopes to be his usual smile, the one that lets him know the scholar is onto his schemes.
“Do your worst, gambler.”
Aventurine’s cock strains against him in an instant. “Ready?” He hears Aventurine speak for the first time since this started, and it’s an eerie, metallic sound that sends a shiver up his spine. The throbbing heat between his legs is almost unbearable now, and Ratio nods.
Aventurine’s cock splits him then, and Ratio lets out something between a gasp and a scream, the dull burn dragging him deep into a pleasurable haze. He blanks out for a moment, and catches a glimpse of the bulge in his stomach before he’s pushed back onto the mattress. Aventurine fucks into him mercilessly, large cock spreading him impossibly wide and reaching depths where he’s never been touched before. Ratio cries out from the sheer onslaught of sensations on his walls, the raw intensity of it shattering any attempt at dignity; in mere moments he’s reduced to a slobbering mess, his high pitched moans an embarrassing affront to his own ears.
It’s too much, and shakily he reaches for his own dribbling cock, painfully erect against his abdomen. Aventurine easily pins his arms, and Ratio is left whimpering as the relentless thrusts keep him a step away from the edge. He’s about to beg when Aventurine picks him up like he would a child, and Ratio forces out a choked moan as he’s now pierced open from below. He can feel himself practically being lifted and pushed down onto Aventurine’s cock, his entire frame shaking from the non-stop sparks of pleasure behind each thrust.
Aventurine manhandles him hard enough to bruise as he pounds into him, squeezing the ample flesh that spills through his fingers. His nails drag over Ratio’s chest, who nearly sobs when the cold tip presses hard into a swollen bud. Wet, filthy sounds fill the room, the rhythmic slaps hardly registering in Ratio’s mind as he’s fucked into a haze. Rational thought is becoming quite difficult, the scholar realizes, and there’s something freeing in just letting go like this - to no longer be Doctor Veritas Ratio with his eight PhDs and 52 classes and a lifetime of aspirations, but a fucktoy for Aventurine of Stratagems.
Faintly, he notes how he’s dropped unceremoniously back onto the bed again, his shaking thighs propped up against him. Aventurine thrusts into him at a frantic pace that becomes increasingly erratic, and Ratio can’t make himself move a finger, his entire body a taut string stretched to its uttermost limit for that sweet release.
“Aventurine,” he calls out warily, before Aventurine’s hand closes around him, the gentlest of touches a teasing scratch against his leaking, neglected cock - and Ratio is gone. White flashes behind his eyes and he comes in a silent scream, back arching as spurts of cum paint his chest. He clenches hard and Aventurine falters, the only sign before warm release splatters against his sensitive walls, the stimulation sending tremors through his entire frame. Ratio feels as if he’s floating, only vaguely aware of the cum leaking out of his twitching, fluttering hole and onto his sheets.
Slowly, things shift back into focus. Ratio is laid gently down on his back, his sweat-soaked hair brushed out of his face as Aventurine looms over him. Exhaustion settles heavy in his limbs and he realizes the mask is still there, unreadable as always.
A shame I can’t kiss him like this, Ratio thinks, before the fatigue guides him into blissful darkness.
—
When Ratio comes to again, he finds himself nested comfortably inside his bathtub. Warm soapy water soothes over his aching senses, the familiar floral scent offering a freshening tug of clarity. Across him, Aventurine curls into himself, fingers idly prodding Ducky back and forth.
Ratio sighs, sinking lower into the tub, feeling every inch of muscle relax and loosen in the warm waters.
Aventurine looks up, the brilliant flash of colors in his eyes a welcomed relief.
“You okay there, Doc?” He asks softly, his gaze falling to Ratio’s chest, no doubt marked by streaks of red all over, “I got a bit carried away there.”
“I - yes.” The scratch in his voice is a brutal reminder of just how carried away they both got during this little scenario of theirs, and Ratio clears his throat in embarrassment. “That was very impressive, gambler. Ten points.” He can feel the tips of his ears burn.
Aventurine blinks, then ducks his head and chuckles, the soft sound doing something inexplicable to Ratio’s chest no matter how many times he’s heard it.
He’s about to close his eyes and drift off again, when Aventurine inches over and clings onto him, as he does. Soon they are an entanglement of limbs, water splashing over the tiles, flinging poor Ducky over the edge.
Ratio wants to be mad, but then Aventurine finally gives him that kiss and all is forgiven. All in all, not bad for a first-time research attempt, Ratio thinks, although he definitely requires more data to come to anything conclusive. For now, the scholar settles with irrational feelings of the heart, as content as he can be.
END