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„I bet I can make you cum faster, using just my mouth.”
A singular eyebrow wanders up at the boldness of Kaeya’s statement, the corner of Childe’s mouth twitching with a flicker of amusement.
“Is that so?”
Kaeya hums his self-assurance, a big smile plastered on his face, the kind that makes Childe’s heart beat faster every time he looks at it. He’s too beautiful for a person, too radiant. With all the atrocities Childe has committed for whatever purposes, all the lies he has told with whatever intentions, he should not be so lucky to call the man in his arms his. But “should” be damned; he will hold on to him as long as he can. Sitting up abruptly Chile forces Kaeya to slip out of the comfortable position of lounging on his boyfriend’s chest and sitting back on his legs. The surprise on Kaeya’s face only lasts for a second before it is replaced with excitement as it registers with him that this means Childe is willing to take the bet.
“I think I can do you faster,” the Fatui challenges.
“Of course you do.” Kaeya smirks.
“I’m willing to walk the talk. Are you?”
“Of course I am.”
“I’ll go first,” Childe announces and Kaeya’s smile widens.
“Of course you are.”
Giddy with excitement Kaeya moves on the bed until he’s the one lying on his back against the pillows, and looks up at Childe with a mixture of amusement and anticipation gleaming in his eye. If Childe feels any kind of performance anxiety he doesn’t show it; on the contrary, he is beaming with confidence and Kaeya reluctantly admits (to himself only) that he might have talked too big too early. Might have. But he’ll be damned if he lets Childe’s confidence intimidate him. He’s used to it by now, for there isn’t a challenge in this world that this man wouldn’t face head on with a smile on his lips.
Childe slots in between his legs and their lips meet in a kiss that holds a lot more fire than the lazy pecks they exchanged a few minutes ago. Feeling generous Kaeya rolls his hips to grind up against Childe, technically offering an undeserved advantage by getting himself aroused, and he’s rewarded for it with a tongue in his mouth, licking into him and brushing against his own. He loves kissing, he could do it all day, and Childe has become particularly good at kissing Kaeya exactly the way he wants to be kissed. He doesn’t tell him that, of course; no need to blow up his ego more than necessary. By the time Childe pulls back they’re both breathless, a thin string of spit connecting their tongues for the length of a heartbeat.
“This is really cute but you’re on the clock, champ,” Kaeya reminds him with a sweet smile. Childe counters it with a smile of his own, one Kaeya could only describe as menacingly. He’s not just confident, he realizes, he has a plan. A flash of light and colors fills the room and causes Kaeya to close his eye and lift an arm over his face protectively. The bed shifts under a new weight, the reason for it dawning on Kaeya even before he opens his eye again. Lowering his arm he looks up at the massive body looming over him and the Foul Legacy looks right back at him.
Any sane person would register this as a terrifying situation for a number of reasons, but for a a number of very different reasons, needless to go into, the only response Kaeya’s body offers is an excited tingling in his tummy.
“What are you planning?” Kaeya asks, suspicion lacing his voice as his mind already begins to connect the dots.
“To make you come,” Childe responds in the same tone he would promise death and demise to his enemies and Kaeya shivers. It should not turn him on as much as it does to hear those words from a monster like the Foul Legacy Champion. And yet, there’s something about his raw voice, the sheer size of him, the way the air around him seems to be charged with electricity. It feels like he’s playing with fire and Kaeya has never been good at nurturing his sense of self-preservation in the face of a risky adventure. Childe’s mouth opens – his maw, really, and out slithers a tongue easily as long as Kaeya’s forearm. The sight of it makes him swallow dryly as a mix of arousal and instinctual fear shoots through his veins and races towards his heart. He can see his last chance to back out of this slipping away from him and deliberately chooses to ignore it. The Cavalry Captain of fair Mondstadt is not one to shy away from a challenge; particularly not one that he issued himself.
The Legacy’s tongue is heavy and hot and it leaves behind a wet trail as it licks along Kaeya’s neck to make its way up into his mouth. It almost feels human, except for its size, albeit a little rougher and Kaeya’s mind runs a mile a minute picturing all the things it could do to him. At first it’s only the tip that wiggles between his lips, parting them and pushing inside without giving him much of a choice on the matter. Kaeya accepts it with a gasp, more or less prepared, his mouth closing down on it and sucking softly. It’s a strange feeling, a little bit like kissing Childe in his regular human shape, but also very very different. Flexible and nimble as it is the Foul Legacy’s tongue does not feel like an extension of Childe but like its own entity, allowing Kaeya to play with it for a moment before pushing deeper into his mouth, sliding into him until it nudges the back of his throat. It takes all Kaeya has not to gag and to his relief Childe does not entertain this little game for long. Clearly he has other plans.
Breathless Kaeya drops his head back into the pillow to get a moment to catch his breath. Childe’s head tilts to the side as he watches him, not unlike a curious dog observing something of which it isn’t sure whether it’s prey or not, adding to the distinctly un-human vibe this shape of him naturally gives off through its monstrous appearance. His tongue is lolling and dripping thick strings of saliva onto Kaeya’s chest. It should be gross, but again Kaeya finds he doesn’t object to it in the slightest.
“Would this be the moment to tell you you’re using too much tongue?” Kaeya teases in order to brush over the state their make-out has pushed him into. He’s hasn’t shed a single piece of clothing yet and Childe already has his body working like a furnace. The laughter he earns for his mockery vibrates through him where their bodies touch and it really makes him comprehend how enormous Childe is in this form, compared to normally. He tries not to dwell too long on the things he might be capable of doing with this body. What he certainly isn’t capable of is undressing him gently in his Foul Legacy form, and Kaeya is grateful for having taken off everything besides his shirt and pants before laying down for cuddles earlier. The sound of popping buttons and tearing fabric fills the room and in a bit Kaeya will lament the destruction of his clothes, but for now all he can do is watch in fascination as large clawed hands peel his pants off his legs, the hard edged iron-clad gloves that cover them feeling rough against his bare skin. He expected him to be cold, but every part of Childe that touches him is surprisingly warm.
He has no time to watch and marvel any longer, for the Legacy’s hands come to rest on his hips and with seemingly no effort flip him onto his stomach. Or, more precisely, on his knees and elbows. Kaeya mumbles something into the pillow about being put on display like this, his thighs parted due to Childe’s body between them and his ass up in the air. No man, no matter how confident, could endure this position without some of the blood in his body rushing to his cheeks.
“Wait,” Kaeya says, pushing up on his arms so he can throw a look over his shoulder.
Bad idea.
Childe’s massive form is towering over him even now that he’s leaning down, his face so close to Kaeya’s bare backside that he can feel his hot breath on his skin. His hole twitches involuntarily, his cock pulsing curiously between his legs. Every instinct in his body is telling him to be afraid, to run, to be repulsed at the very thought of what they’re about to do, but something else inside him wins over. A twisted shameless need rooted deep inside him, the same that, at its core, is what guides his hand to touch himself when he thinks of things he shouldn’t, or makes him share his bed with Childe in the first place. A physical, primal need that wins over any fear or reason and holds its own reigns.
“You’re cheat---ahh~”
That wicked, wicked tongue laps between Kaeya’s legs, drawing a sloppy line on his inner thigh and over his balls all the way up to his hole. It leaves so much slabby saliva in its wake Kaeya can watch it drip down his skin onto the bed like clear honey when he lets his head drop to look between his legs. He trembles with arousal. He expects it to be rough when it wiggles inside him, the size of it alone reason to be worried, but it’s all slippery and slick and it disappears inside him embarrassingly easily. Kaeya moans so loudly it surprises even him. Childe doesn’t push in deep at first, just a few inches, as if he’s testing the waters, but it’s already deep enough to make Kaeya’s head spin. It’s nothing like a finger or a cock; it’s too flexible, too soft and yet muscular at the same time. The sensation of its thick muscles contracting inside him sends uncontrollable jolts of pleasure through his entire body.
And Childe doesn’t waste any more time.
His hands rest on Kaeya’s waist, fingers so long they almost close around him completely, and holding him still as he works his way deeper. And deeper. Kaeya prides himself on his ability to be quiet and controlled when he has to, but right now he’s pressing his face into the pillow to muffle the pathetic gasps that pour out of him and no amount of self-control he can muster could save him from it. The tongue putters around left and right as it thrusts into him, stimulating the tight ring of muscles at his entrance that tries to clench down on the intruding force against all odds. It brushes his walls going deeper yet, until it pokes his sweet spot unexpectedly, pressing up into it hard, and draws a loud moan from Kaeya that his pillow fails to swallow entirely. His back arches and his hand slams down hard on the mattress with a lack of anything better to grab or manhandle.
His half-hard cock roars to life, throbbing as it hardens so quickly it actually makes him dizzy. He curses under his breath, panting into the pillow under his face that’s grown damp from his breathing. Just guessing from how much of it Kaeya can feel he figures Childe’s tongue is inside him about as far as his dick would reach now. It matches the stretch he feels where the tongue is currently at its thickest and he thinks back on the sheer length of it with a hint of panic rising beneath the arousal. The thought of taking it all was perhaps better in theory.
Part of Kaeya hopes Childe won’t go that far, the other part vibrates with excitement at the prospect of it. But something tells him it won’t be his choice anyway.
Seemingly dissatisfied with Kaeya’s response, although he got him hard and panting within seconds, Childe continues his efforts seamlessly. His tongue wiggles a little deeper, its thickness a constant sliding pressure against Kaeya’s prostate that makes his hips jerk so violently Childe’s hold on him tightens into something bordering painful.
“F-uck..” Kaeya gasps. His hands are closed to fists around the pillow, trembling in their grip, and his eye is pressed shut in an attempt to channel all his attention into keeping his composure. He’s going to cum. Hard. And they only just started less than two minutes ago. The indignity of that is almost harder to bear than the overstimulation Childe is providing. Almost.
With his body heating up and his mind growing hazy Kaeya can’t tell anymore if Childe is trying to reach even deeper or just moving around inside him to drive him mad, but he’s sure he can feel Childe’s tongue in parts of him deeper than anything’s ever been inside him, grinding, pressing, lapping against his prostate without missing a heartbeat. He feels like he’s about to pass out, and part of him wishes he would. His hips are trembling in Childe’s hold, desperately caught between trying to push back or to crawl away, both to no avail. His cock is so hard it aches, curled up against his stomach and leaking pitiful amounts of pre-cum against his skin and onto the bed. A single feather-light touch would be enough to push him over the edge and he silently begs that Childe won’t get that idea too. The sounds that leave him don’t even sound like him anymore but Kaeya is too far gone to be embarrassed by them. One moan is barely distinguishable from the next, all drawn together in a desperate litany of unbridled pleasure only quieted by the pillow in his face.
Fuck, did he blow that bet.
It takes all the willpower Kaeya has to hold back but even so he is rushing towards a thunderous finish at a record pace. He shoves a corner of the pillow into his mouth and bites down hard; tries to remember how to breathe as his body pulses with heat, pleasure pooling hot at the pit of his stomach, the need to let go and cum like a terrible itch that spreads into each of his limbs. Just a little bit longer. Just a little..
Childe’s tongue pulls back unexpectedly and Kaeya holds his breath – until it thrusts back into him, making him see stars. Childe knows that he’s about to break; Kaeya can tell by the way the very air around them turns smug. Bastard.
Suddenly the world shifts and Kaeya shrieks when his lower body is being lifted into the air, his knees losing contact with the bed altogether. Childe is holding him up by his thighs, spreading them apart a little more than before and with a purr that shouldn’t come out of a monster like him and travels down Kaeya’s spine he pulls him all the way against his maw.
“Wait—“ Kaeya begs helplessly. He shouldn’t expect Childe to stop now, even if his pleas were serious. The Foul Legacy was not created to be merciful and modest. It is Childe’s insatiability personified, the harshest of his traits pushed to their very limit. And he’s the idiot that challenged it.
The stretch is worse than before but Kaeya is so loose by now and so wet from the endlessly dripping saliva that the pain is only a faint sting. He bites the pillow for dear life, his arms curled around it while the rest of his body is held up like he’s a doll weighing nothing at all. The Foul Legacy’s tongue rolls up against his prostate once more and this time it focuses on that spot purposely, rubbing up hard, faster and more precise than fingers ever could. It is hot and rough and for a moment Kaeya becomes hyper-aware of every twitch of muscle inside it, every bump or unevenness on its surface - and then everything explodes in a sea of white.
He comes with a scream.
He comes so hard his cum shoots up all the way to his collarbone, his cock visibly twitching as thick white ropes are forced out of it untouched. His toes are curling, back arching even more than the position Childe holds him in forces him to. For a moment or two there are no thoughts in his head, only pure pleasure and adrenaline in abundance. A second later the fog begins to clear and Kaeya’s moan breaks off into whimpers when Childe doesn’t let go even after he came, his tongue still buried inside him, drool dripping from his maw and running down Kaeya’s cock and thighs.
Kaeya lifts his head off the pillow and pushes it aside to reach for the far edge of the bed instead, trying to pull himself towards it and away from Childe. He barely gains a few centimeters before he’s pulled back by the large hands still wrapped firmly around his thighs.
“S-stop..” he whimpers when the thick slippery tongue starts to move, fucking him slowly, some part of it nudging his prostate every time it thrusts into him. “Stop!” Kaeya calls out before he tenses all over, gripped by another half-orgasm that forces a few more pitiful drops out of his cock. “Please! You win— stop..” he gasps as Childe pulls him back so far his fingers lose their grip on the edge of the mattress.
Childe flips him over once more and Kaeya feels the dampness of the mess they made on the sheets against his shoulder blades. With a violent blush spreading on his cheeks he realizes Childe didn’t even bother pulling out of him before turning his body around. His legs hook around Childe’s broad shoulders and now nothing stands between Kaeya and the depravity of watching himself be devoured by the Foul Legacy anymore. He moans, perhaps from the sight, or perhaps because Childe’s tongue is wiggling inside him again, tickling a spot in him so deep he feels like he is going insane. Then it thrusts up and the last thing Kaeya sees before his eye is pressed close and his head falls back is the way his stomach bulges slightly. His thighs close tightly around Childe’s shoulders, parts of his mask digging into the supple flesh painfully. He cries out hoarsely, hands clutching Childe’s fingers and holding on to them as much as trying to tug them away from his skin.
“Please..” he pants and finally Childe takes pity on him. A considerable amount of thick saliva leaks out of Kaeya when he withdraws his tongue, and a considerable amount of it undoubtedly stays behind inside him. He feels the warm wetness of it when his muscles clench around the sudden emptiness and it fills him with a hint of shame. He looks up to watch the long dexterous limb lap at his inner thighs and wander up to his cock, breath hitching in his throat at the raw intense feeling of it.
“Too much,” Kaeya whines but Childe’s tongue plays with him regardless, curling around his oversensitive member and teasing the slit with its thin tip. Its strong muscle is like a hand’s firm grip around him and to both of their surprise it manages to force yet another orgasm out of him, dry and pathetic, drowned in a choked moan and a blur of tears falling from his eyes, wetting his eyepatch. He comes down from it trembling when Childe finally lets go and lowers him back on the bed, his touch almost careful now. Mildly embarrassed by how thoroughly wrecked he feels Kaeya brings his hands to his face and wipes his cheeks as another flash of light fills the room.
“You cheated..” Kaeya mumbles tiredly into the sheets, too drained to mind the drool and cum on them in that moment. His face is beet-red and hot when Childe drops down next to him, a smug self-satisfied smile on his very human face.
“Did not. You didn’t set any rules,” he states and Kaeya groans. “Good luck trying to beat that. I don’t think I’ve seen anyone come that fast since I was a teenager,” Childe teases. Kaeya slaps a hand on his chest which only earns him a laugh, but a moment later Childe swats it away with a yelp. Where Kaeya’s hand touched his skin it turned red and is covered in little ice crystals that are already beginning to melt against the warmth of his body.
“You’re a sore loser,” Childe points out and Kaeya huffs.
“I didn’t lose. You cheated.”
“Did not.”
“Did too.”
“Fine, then let’s go again, without the Foul Legacy this time.”
Kaeya sits up, ignoring any and all protests his body immediately screams at him.
“Oh, it’s on.”
“Brace yourself, this is gonna blow your mind.”