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Tanjirou is by no means a weak child. 


This, Kyojurou knows. Even if it weren’t for the hard-won lines of muscle or the bumpy calluses of his hands, the most vital evidence of this is in the boy’s eyes. Fiery and constant, resolute, clear. A hefty goal weighing upon a young boy’s shoulders, his heart’s shards in a box, his feet carrying forward with nothing but fierce determination. Kyojurou has rarely seen the same strength in older, weathered men.


But he is a young boy, still.


As Tanjirou pants under him, writhing and whimpering, he can’t help but let his hands wander. The boy is splayed on his futon like a gift, his nemaki long undone with its sleeves just barely holding on to his shoulders. A glance down reveals his leaking cock, painting stripes of white on his skin. He swipes a thumb through the mess, captivated in how it smears over flushed, heaving, tan skin. It does little to distract from the way his hand covers more than half of the boy’s abdomen, and it makes fire surge anew in his belly.


He’s so small. It’s intoxicating.


“Rengoku-san” he calls, and Kyojurou tears his eyes away to look at him. His face is flushed pink, and he senses some embarrassment being the cause of it; they’ve barely done anything, after all. It thrills him how sensitive he is, how the boy’s cock is aching for release after little more than wet kisses and heavy petting. Is it due to his inexperience, or his constant eagerness for his attention, he wonders. “What are you doing?”


He smiles indulgently. His hands continue their exploration languidly, feeling the dips of skin where his muscles contract, fingers gently grazing old wounds. Eventually, he reaches his hips, spread wide on either side of him so Kyojurou can fit between his legs. 


“I’m just wandering.” he finally answers, chuckling when he senses a spike of irritation from his lover. “And, well, wondering…”


“Wondering about?”


He lifts the boy’s hips, eliciting a yelp, and cocks his head playfully at the sight.


“If it’ll fit.”


Tanjirou’s face burns. Kyojurou doesn’t miss how his eyes flicker to his groin, his own nemaki doing little to hide the tent it pitches. Something in his face flickers, but it’s gone before Kyojurou can make out what it means.


“We don’t have to do it if you’re uncomfortable, my boy. I can just suck you off as usual.” it’s not a lesser trade-off, in his opinion; the feel of Tanjirou’s cock in his mouth is something he finds himself craving when they’re apart. The boy gives off a distinct musk, warm and alluring, and the faces he makes when he comes is truly something to behold. He’s more than happy to reacquaint himself. 


Tanjirou squirms at the latter remark, bashful at the older man’s bluntness. It’s endearing how demure he is before he gets really into it, shy as a young bride. His eyes trail back on Kyojurou’s clothed cock, and it takes a moment before his quivering lips answer.


“I want it.” he breathes, pupils dilated and chest heaving, “It… If you stretch me out, it should be okay. I-I’ve been… practicing.”


Kyojurou’s mind goes blank.




Tanjirou looks away, holding the back of his hand up to his mouth like it will somehow abate him of his shyness, “I’ve been wanting to try,” he forces out, “I want to know what it’ll feel like with you inside me. For us to… be one, with one another. There’s no one else I would want that with.”


Kyojurou has to close his eyes at that, suddenly overwhelmed. Between his throbbing cock and Tanjirou’s shy admission, sweet and potent and alluring, it feels like there’s too much in his chest fighting its way out. A bottleneck of his affection, surging.


“Show me.”


“Show you…?”


“How you practice. It’s my duty as your aniki to see you through, is it not?”


Tanjirou lets out a short huff, exasperated but fond, “Rengoku-san, now is not the time to… nevermind.” he sighs, a small smile playing on his lips. Kyojurou hands him the bottle of oil he’s kept to the side, and sits back on his haunches, expectantly.


It doesn’t take long for Kyojurou to come to the searing revelation that Tanjirou has done this many, many times before. His practiced fingers coat themselves in the oil and reach between his legs, his thighs parting further. A single digit rubs at his entrance, wetting it liberally before it plunges in, and Kyojurou wills himself unblinking.


Tanjirou is extraordinarily good at keeping quiet through his ministrations, biting his lip and breathing heavily through his nose. He starts fucking his fingers into himself at a steady pace, adding more digits as he feels himself getting loose. The implications of his silent ease are not lost on Kyojurou.


“You can let it out,” he murmurs, hands gently stroking at the skin of his hips, “It’s just us. I want to hear you.”


Three fingers in, Tanjirou looks at him, wide-eyed. Kyojurou’s eyes crinkle as he smiles, his hands once again finding the back of the boy’s hips and lifting, smoothing over his skin to the back of his knees, folding him nearly in half.


“Wait, Rengoku-san--” he cries at the sudden change in position, choking out a gasp when his fingers manage to crook just right. His whole body trembles, quiet whimpers escaping red-bitten lips. Precum spurts from his cock, adding to the mess on his belly and trailing up to his pectorals. The image of seeing Tanjirou come in this position, his own cum spattering over his own face, flits into Kyojurou’s mind unbidden.


“I’m ready,” he whispers, though his fingers have started to thrust back in again, his pace increasingly desperate, “I-I don’t think I can hold out much longer if you don’t put it in me now.”


“We have all night,” he reasons, and fights down a laugh when Tanjirou balks, “Surely a young, spritely boy like you can handle a few rounds?”


“But I--” and his eyes are glassy, shimmering in the dim light, “I-Inside?”


Kyojurou’s face twitches, the squelching coming from Tanjirou’s fingers making itself evident in the space between them. He inhales deeply, taking in how Tanjirou is spread beneath him, open and inviting, rutting into his own fingers like an animal in heat. 


“Of course. As many times as you like.” he leans in, folding the younger boy further, “As many times as you can take.”


Tanjirou’s breath hitches, his fingers stopping for a moment. Kyojurou sits back, his grip on his legs steady.


“Go on, then. Come for me.”


The boy’s eyes glaze over, and Kyojurou hums in interest. Learning what buttons to press to unravel his dear boy is an ongoing process, but one that delights him at every turn. Taking a breath, Tanjirou resumes his thrusting, the angle allowing him leverage to hit his prostate at every plunge. It doesn’t take long for that desperation to return, for Kyojurou’s mouth to water as Tanjirou pace grows increasingly frantic.


“Rengoku-san,” he pants, open-mouthed at last, pink tongue resting on his lower lip, “ Rengoku-san .”


“Do you think you can add another, my boy?” he asks, and Tanjirou whines, “To get yourself ready for me?”


He does, and at four digits Kyojurou has to swallow thickly at the way his hole stretches.


He’s so small.


“What do you think of, when you do this to yourself?” he murmurs, pressing a kiss to his calf, “What makes you so desperate to try?”


It feels almost cruel, to be so coherent when Tanjirou looks like he’s worlds away. To watch Tanjirou’s eyes threaten to roll up into his skull as he fucks himself on his own fingers, his free hand fisting the sheets tight. He marvels at the way Tanjirou refuses to touch his cock, unwilling to do so unless he asks.


“Y-You,” he chokes out, breath coming in short pants, “Every time I have you in my mouth I--I wonder. What it would be like.” He looks up into Kyojurou’s eyes, letting the collecting tears fall.


“You’re so big , Rengoku-san.”


For the second time that night, Kyojurou’s mind goes completely blank.


“Every time I have you in my mouth it--aches,” he continues, his pace slowing to a stutter, “Sometimes I wonder how far down my throat it’ll go, if I take it all in.”


The question is out of his mouth before he can think, “Have you been practicing that as well?”


Tanjirou bites his lip and doesn’t answer. Blood roars in Kyojurou’s ears.


“Are you close?” 


He nods.


“Then hurry,” he purrs, his aching cock making itself evident as he slowly ruts against his crack, the tip clothed and dripping through the fabric, “Come for me.”


Tanjirou whimpers at the feel of his cock on him, and obediently follows through. It’s dizzying, how enraptured Tanjirou looks like this, giving in to pleasure in a way Kyojurou has never seen before. The way he chases his release like a man possessed, like an animal in heat. Tunnel vision to a singular goal, as he is known.


“You’re so beautiful, my boy,” he croons lowly, listening to Tanjirou moan and whine, “I can’t wait to stuff you full. You’ve worked so hard, getting yourself ready for me; I have no doubt you’ll look gorgeous split open on my cock like you deserve.”


He leans in once more, folding him tighter. His eyes glint in the low light, wide and focused, like a hawk trained on its prey.




Tanjirou cries out, his voice breaking midway as he’s granted his release. Kyojurou watches avidly as cum spurts from his cock, and he’s right in that some of it lands on Tanjirou’s chin and collarbones, its contrast stark against the blush-pink skin. He swallows, mouth dry, as Tanjirou convulses against the sheets, writhing wildly from the force of his orgasm.


“Rengoku-san, Rengoku-san, ” he whines, pleasure-drunk, and Kyojurou almost suggests they stop for the night when Tanjirou’s eyes meet his, desperate hunger in his blown pupils.


“Inside,” he pleads, weeping openly. He retracts his fingers from his abused entrance and spreads them on either side of his rim, stretching himself open, “Your cock, please. Please.


It doesn’t take long for Kyojurou to disrobe himself enough to pull himself out, the tip red and leaking copiously. He allows himself a few strokes, shuddering at the contact after denying himself for so long. Tanjirou, having been freed from his grip at last, hooks his elbow under one of his knees, splaying himself open while his other hand plays with his rim. When Kyojurou leads his cock to his entrance, he spreads his hole open once more, ready to be taken.




Kyojurou pushes in, and Tanjirou keens from the stretch. Already, it’s evident that Kyojurou is still too large for him to take, despite the preparation. All it does is make Tanjirou want more of it.


“Please,” he repeats, panting open-mouthed, “I want all of it, I can take it.”


Kyojurou growls under his breath, his muscles tensing as his hands grip those small, small hips. He’s the elder between them, so he should be making the final call for what Tanjirou can and can’t take; and he has. 


But Tanjirou always has a way of making him a little selfish.


In one thrust, he stuffs himself in completely. Tanjirou’s back arches, unlocking his knee so he can fist both hands into the sheets. A choking noise escapes him, breathy whimpers and pleased moans filling the air. He’s so tight it’s almost suffocating, and Kyojurou has to take a moment to collect himself when he sees the little paunch he’s made low on Tanjirou’s belly, the faint outline of his cock visible through his skin.


“I knew it’d fit,” Tanjirou slurs dreamily.


Kyojurou feels like he might not leave this night fully sane, at this rate. He’s vaguely alarmed to realise he doesn’t mind.


His hands drift to Tanjirou’s knees once more, like a man possessed, like muscle memory returning to him, and he folds the boy in half once more. He swallows, sweat beginning to pour down his hairline, watching as Tanjirou calms.


“You can let go, too,” Tanjirou says, a gentle, calloused hand reaching up to stroke his cheek. “I want you to let go. I promise you I’ll feel good.”


So he does.


He can’t help but be frightened of himself, when he’s with Tanjirou. The ways in which the boy so masterfully makes him want so luxuriously, so indulgently, so fiercely, without guilt piercing his heart--it’s terrifying. Tanjirou gives him so much in just a glance; to be given his heart, his body, makes him almost sick with gluttony. But he craves and craves and craves, and Tanjirou sates him twicefold.


Of course, that’s not to say he doesn’t bring out the same in Tanjirou. He’s not unaware; it’s hard to be.


His hips snap at a brutal pace, bottoming out at every thrust. He watches, enraptured, as the bulge in Tanjirou’s stomach deflates when he reels back, marveling at how Tanjirou has given himself so fully to him. He feels like he’s rearranging the boy’s guts with just his cock, molding his body to its shape, and the boy merely spreads his legs wider. It’s power he’s not used to having, and he finds himself drunk with it.


“Gorgeous,” he breathes, achingly close. Tanjirou’s hair is splayed upon the pillow in a halo of burgundy, his mouth open and panting, his tongue lewdly hanging from his lips. He’s gotten much louder now, squealing when Kyoujurou thrusts in especially hard; it’s no trouble finding his prostate, being so big. He hits it on every thrust in, making Tanjirou near-delirious with pleasure.


“I’m going to fill you up, my love,” and Tanjirou gasps, walls clenching, “I’m going to stuff you full of my seed until you’re dripping. When we are apart once more, and you fuck yourself on your clever, clever fingers, I want you to think back to how this feels.”


“Please,” he moans, a steady stream of tears leaking down his cheeks as he’s jostled from the thrusts, “ Please .”


“Even if I weren’t so in love with you,” Kyojurou continues, his thrusts growing erratic, “I think I would’ve wanted to keep you all to myself all the same. How could I not, when it feels like you were made to take my cock?”


“Yes, yes,” Tanjirou pants, his eyes wandering down to his belly, widening when he sees the way it bulges from the intrusion. He pants harder, saliva dripping from the tip of his tongue as he’s fucked, fixated on the way his body yields to cock. Even if I weren’t so in love with you , he wants to say, I think I would have been ruined for anyone else all the same.


It takes a few deep thrusts before Kyojurou meets his own release, slamming home into the small body beneath him. Tanjirou’s eyes roll back into his head, his mouth gaping as the cock inside him grows bigger shortly before it starts pumping cum into his hole. Kyojurou releases his grip on him and collapses, his forearms on either side of his head keeping him from fully crushing the boy. He groans loudly, feeling Tanjirou’s walls milk him for all he’s worth, filling him to the brim.


Kyojurou’s eyes flicker up to Tanjirou’s, dazed and distantly taking note of the cum on the boy’s cheeks. There’s a bigger mess smeared over his belly and chest, and Kyojurou wonders how many times the boy came while he was fucking into him. He can’t bring himself to feel any kind of remorse.


Tanjirou, when a little more of him returns to himself, looks back and smiles. He cranes his neck forward for a kiss, and Kyojurou can’t help but close the distance and peck him, sweet and quick while they regain their breathing. Tanjirou, chest heaving, can’t help but giggle, the flush of their lovemaking rendering him giddy.


“You want to keep me all to yourself, do you?” he teases, and Kyojurou’s face heats. 


“Hm,” he grunts, smile on his lips as he shifts--shuddering at the feeling of cum seeping out from his hole, from what little space exists between them “Is that a problem?”


“Not at all,” he smiles, slightly wobbly in his dazed state, “I’m happy. I’m all yours for the taking.”


Despite himself, Kyojurou’s cock throbs. Tanjirou’s eyes glaze over.


They have all night, still.