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They have to dodge three different teams of overexcited genin between the mission room and their apartment, when all Izumo wanted was to go home and relax now that their mission is done. "Tch, the month after graduation is always so hectic," he complains, landing on the apartment balcony and reaching for the chakra seals on the door.
"Give them a break, they're excited," Kotetsu says, from close enough behind Izumo that anybody else would be risking a stabbing. "It's a big deal, getting out of the academy and being able to really call yourself a shinobi at last. Of course it makes them a little rambunctious. Don't you remember how much trouble we were at that age?"
The seals come open and Izumo slips inside, toeing off his sandals. "I remember how much trouble you were, definitely," he says, but the memory brings a smile to his face all the same. "I kept having to go track you down when you were off messing around somewhere instead of paying attention to our assignment."
Kotetsu grins. "And in between assignments, too," he says. "You couldn't get enough any more than I could."
"At least one of us grew out of being an irresponsible brat," Izumo says.
"You wouldn't have me any other way," Kotetsu says, and he's right. He wouldn't be Kotetsu if he were serious all the time. There's a crackle of chakra and the smoke-puff of a transformation. "Unless maybe you miss those early days?"
The smoke clears and Kotetsu looks ten years younger, lanky and not yet grown into his full height, his crooked grin somehow even cockier on a face that hasn't quite lost its baby fat. "I don't see any difference," Izumo says, doing his best to keep a straight face. "You haven't changed a bit."
Kotetsu makes a face that would have gotten their jounin sensei thinking up new and more creative ways to punish them, and changes back. "Nah, you're right," he says. "You're the one who needs to remember what it felt like."
That idea, for some reason, makes Izumo stop in his tracks. His hands start flipping through the seals to sound-proof the apartment so they won't scandalize or annoy the neighbors. "You'd stay as you are and I'd change, hmm? You want to show me how it's done?"
"Ah, I don't know," Kotetsu says, rubbing the back of his head. "I'm not so sure I'm cut out for the sensei role."
They could both transform, true—relive those early days together—but there's something that makes Izumo pleasantly shivery about the idea of him transforming while Kotetsu doesn't. "You could be the kind of sempai who sets a bad example," he suggests.
"Could be?" Kotetsu echoes, clutching his chest as if he's heartbroken.
"Fair enough," Izumo says. "You're already a terrible example." He brings his hands together for the transformation jutsu. "I hope you'll give me a very thorough demonstration." He gathers his chakra, focusing on the age he wants to recreate, and runs quickly through the seals.
There's always a moment of strangeness, settling into any kind of transformation—it's usually no big thing, and in the field it's easy enough to ignore. Being able to keep your head when things get strange is one of the most crucial survival skills for a ninja. But there aren't any threats here, so Izumo takes a few seconds to think about the strangeness: ten years younger and he was just starting to hit his growth spurt, a good head shorter than Kotetsu is now. He felt gangly and awkward all the time, and he still feels a faint touch of that, even now that he knows he did grow out of it. And the things that were happening to his hormones....
Well. He gets as far as wondering will Kotetsu really be willing to screw like this? and by the time he's mentally finished the question his cock is hard enough to be embarrassing.
"Something the matter?" Kotetsu asks. There's a sofa in their living room, and he sprawls on it, cocking an eyebrow. "You look a little uncomfortable."
Are they roleplaying? Izumo decides he'll assume they are. "I just...I feel like it's easy to get distracted lately," he says. "I can barely concentrate on my training." He thinks back, remembers what it was like that giddy summer when he and Kotetsu discovered how much more exciting it was to touch each other than themselves. "There's this guy that I can't stop thinking about."
"Always trouble," Kotetsu says. "Come here. Tell me about him."
Izumo tries not to smile. Fishing for compliments, is he? "He's kind of a slacker, but he's talented when he actually tries. And he's hot." He sits down on the couch, one leg folded under himself. This close to Kotetsu, the difference between them becomes really obvious—they both did so much growing up over the last ten years. "And he's older," Izumo says. That's still a lot more exciting than he would have expected it to be.
Kotetsu shrugs. The light in his eyes seems more curious than anything. "Nothing wrong with that," he says. "You get an older boyfriend, he should know what he's doing, right?"
"Well." Izumo chews his lip. "If he's willing to give me a chance. What if he thinks I'm too young to be worth his time?"
"Won't know till you ask him," Kotetsu says. He grins. "If he's smart, he'd be happy to show a cute young thing like you how it's done."
Izumo barely stops himself from squirming, and his face feels hot. Who would have thought a little misuse of jutsu could do this to him? They've been sleeping together for years, but all of a sudden he's blushing like it's the first time all over again.
If he's remembering right, his transformed age is younger than he was the first time they actually had sex.
"You're right," he says. "A shinobi should have courage." He rocks forward onto his knees, crawls into Kotetsu's lap, and kisses him.
It feels so different. Kotetsu is bigger than he is, much broader through the shoulders, stubble rough against Izumo's mouth. Izumo kisses clumsily, only half faking it—he really is off-balance, and it isn't hard to translate that into action. Kotetsu leans into him, taking control easily, sliding both hands up Izumo's thighs to palm his ass—his hands feel so big—and drag him closer.
"Sempai," Izumo breathes as he drapes his arms over Kotetsu's shoulders, mostly just to see if it will make him feel as shivery as he thinks it might. It does: suddenly this isn't the comfortable balance they've had for years, but something illicit and a little dangerous. And Kotetsu groans at the word, the same way he does when Izumo bites down on the inside of his wrist or the nape of his neck. Izumo leans close enough to murmur right in Kotetsu's ear. "Will you teach me, sempai?"
Kotetsu's hands tighten, pulling Izumo down into his lap hard. "Yeah," he says, his voice raw. "I'll show you everything you've been missing."
Izumo whimpers, squirming in Kotetsu's lap as Kotetsu starts tugging his shirt up. Usually they're well matched, a balance for each other; they always have been. This game throws that balance off, means he has every reason to just surrender and let Kotetsu lead—to let himself just be pleasantly overwhelmed by Kotetsu's heat and strength and the breadth of his hands.
He arches his back as Kotetsu peels his shirt off, and before it's even fully gone, while it's still trapped around his wrists, Kotetsu is leaning in to lick one of his nipples, mouth closing around it to suckle and almost bite. Izumo hisses, tossing his shirt out of the way so he'll have his hands free to hold on. He gets a grip on Kotetsu's hair and pulls, and Kotetsu bites down in return.
"Look at you," Kotetsu says when he pulls back. He runs his hands down Izumo's chest, palms splayed against his ribs. "So young. You don't have any scars."
That isn't entirely true—even as kids in training, shinobi get in a certain amount of trouble—but his skin is smoother like this, less marked. He looks soft without his scars, doesn't he? "Be gentle with me, sempai," Izumo says, even though he'd be a little disappointed if Kotetsu did entirely.
The face Kotetsu makes, though, like he's trying not to just go off in his pants—"I'll try," he says, his voice low and husky like it's going to take effort to hold himself back, and that's the best answer.
Izumo bites his lip to stop himself from making demands. He's the young one, the inexperienced one. He's letting Kotetsu lead.
"Nervous?" Kotetsu asks. He leans in close, hands on Izumo's bare back, breath hot against Izumo's jaw. "Or impatient?" His teeth close around Izumo's earlobe.
"Please," Izumo says. "Oh please."
Kotetsu laughs. "How could I refuse?" he says. "Kouhai."
He transports them to the bedroom, a silly waste of chakra when they could walk there in three steps, but Izumo doesn't care right now. Kotetsu—his Kotetsu-sempai—is laying him out across the bed, tugging his pants open and skinning them off his hips. He arches his back to make it easier for Kotetsu to strip him. And Kotetsu does, dropping Izumo's pants over the side of the bed and then sitting back to just look at him for a minute, eyes dark and hungry and warm.
This throws their balance further, Izumo thinks. He's stripped bare, wearing no insignia, no signs of who he is; like this, he's just a boy. Kotetsu is an adult, a shinobi, still wearing most of his weapons, shins bound and flak jacket protecting him. He reaches for its zipper and Izumo shakes his head just slightly, a small enough motion to ignore, if Kotetsu really wants—
Kotetsu grins, and lets his hand fall away. "Kinky little brat," he says, leaning down to pin Izumo under his weight. His jacket is rough against Izumo's bare skin, and Izumo's moan gets swallowed by the next kiss. Izumo squirms beneath him, letting the pressure of Kotetsu's hips press his thighs apart. Vulnerability should be terrifying, but it's different like this, different when it's Kotetsu, so he keeps seeking more.
And maybe he's trying to say that out loud, because Kotetsu echoes him, "More," quiet and fierce, when his hand slips down between them: fingertips trailing down his cock, cupping his balls for just a moment, then sliding further back. "Do you want to give this to me, kouhai?" he asks.
Izumo bites his lip, trying desperately to find enough self-control not to come all over himself like the overeager teenager he currently is. "Please, yes, sempai," he says. "It's for you."
"I'll take good care of it," Kotetsu promises, and his leer makes that sound absolutely filthy. Izumo flushes hot as Kotetsu sits back to reach for the bottle of lube in the nightstand.
"How should I, ah," Izumo asks, watching Kotetsu slick his fingers. "Where do you want me?"
"You should stay right there, so I can see your face," Kotetsu purrs. "Just lift your knees for me."
So he can watch Izumo be overwhelmed by this and still make him spread himself open for the taking. Izumo lifts his knees, wraps his hands around the backs of his thighs and holds himself open. The position is practically begging for it.
Kotetsu likes what he sees, from the slow smile that spreads across his face. "Just like that," he says as he slips slick fingers into the crack of Izumo's ass. "Been a long time since I've had a virgin," he says. "And you're going to be so tight, aren't you?"
Izumo nods frantically. He can feel Kotetsu starting to push, and he knows perfectly well how to breathe through it to make it easier. The desperate, helpless moan that goes with the exhale is optional, but it makes heat flush across his skin and flare in Kotetsu's eyes. And the stretch feels—he was expecting it to be different; he knows Kotetsu's cock is going to feel bigger when he's smaller and slighter than usual himself. But already, it's a little more than he expected. He squirms, and Kotetsu groans.
"Sempai," Izumo breathes, "Ah—"
"Yeah," Kotetsu says. "Yeah, you're going to be amazing, just like that." His free hand slides up the inside of Izumo's thigh, then ghosts along the underside of Izumo's cock. "This going to be too much if I play with you, too?"
"I—" Izumo hesitates, then nods. "I feel like I'm—" he laughs, helplessly, breathelessly. "Feel like I could go off any second."
Kotetsu grins. "Let's try to wait for a second when I've got my cock in here, then," he says, crooking his finger upward and making Izumo writhe.
"Yes," Izumo pants, "yes, ah, you bastard."
"Language, kouhai," Kotetsu says mildly. He winks. "If anyone's going to be using foul language here, it ought to be me."
Izumo grins back, despite how overwhelmed he feels already. "Maybe you should, ah, s-show me how it's done, sempai."
"Open up for me," Kotetsu says, leaning over him so Izumo can really feel the size difference between them right now. "Get your sweet little virgin asshole nice and relaxed so I can stuff it with cock."
Izumo croons, and rocks down to meet it as Kotetsu presses another finger into him. It's going to be so much, good but overwhelming, and Kotetsu keeps talking as he fingers Izumo's ass—telling him how sweet he is, how easy he is, how clearly he needs somebody to show him how to do this if he wants it so damn much. Izumo says yes, yes, it's true, it's all true, he needs it so much, please, sempai.
For all that he's begging for it, he still feels a little thrill of surprise when Kotetsu pulls out, leaving him stretched and empty and watching wide-eyed as Kotetsu strokes more lube over the length of his cock. "Ready for me now?" he asks.
"Yes," Izumo breathes. "Yes, oh please," and his voice cracks. It's so easy to play the role, so easy to feel that desperate, when his body hums with teenage hormones. How did he ever pay attention to anything the first time he was this age?
Kotetsu leans down over top of him, pressing his thighs to his chest, bending him almost double and making his hips cant upward. The slicked head of his cock nudges at Izumo's hole, just barely pressing. Izumo takes a deep breath, lets it out as Kotetsu starts to push—and he can't quite help the desperate whimper that escapes him at the stretch.
"You all right?" Kotetsu asks, holding steady, just barely inside him. "I can stop if you need me to." I really hope you don't need me to, his eyes say.
Izumo shakes his head. "It's okay," he says, and his cheeks burn as he goes on: "You just—you just feel so big, sempai," and he sounds like every blushing virgin ever to grace the pages of Icha Icha but he doesn't care, because it sends a thrill down his spine to say it and then another when Kotetsu groans like the words are more than he can handle. "Sempai, please," Izumo says. "Please f-fuck me."
"Yes," Kotetsu moans, like it's ruining him. "Let me take care of you, kouhai." He rocks deeper, until Izumo feels like he couldn't possibly take any more—and then pauses there, with Izumo so full it feels like he barely has room to breathe. Izumo is trembling, or maybe they both are, nerves taut and humming, cock aching stiff.
Then Kotetsu starts to move, slowly, easy thrusts that are still almost too much to take. He hooks Izumo's legs over his shoulders and the pressure is just perfect like that, makes Izumo gasp and whimper, clinging to Kotetsu's arms as tight as he can. "Yes," he says, "yes, oh, sempai, you—" he makes himself stutter for the sound of it— "your c-cock feels so good in me."
"Yeah," Kotetsu says, speeding up his thrusts, so the fullness and burn are hovering just on the edge of really too much, maddening, but still right at that angle that drives Izumo higher every time he pushes deep, "yeah, you love it, don't you? Gonna make you come, sempai's cock stuffing you?" Izumo can't even find words, nodding agreement. He's wound so tight, shaky as he tenses toward it, and Kotetsu's punishing that spot—and still talking: "You look so fucking good like this—should have fucked you when you really were this age, hha, you—you're close, huh, tell me you are, feels like you are—"
And Izumo is, so much closer than he should be without either of them touching his cock, but he feels like a trap set to spring at the first wayward breath, and then on Kotetsu's next thrust his stomach brushes against Izumo's cock and that's it, that's all it takes, that one suggestion on top of the pounding he's getting, and he puts the silencing jutsu to good use, sobbing and moaning as he comes without a hand on him.
Kotetsu curses, breathless and stunned, his thrusts turning sharp and short, barely pulling out before he presses in again, and the aftershocks just keep going, won't let Izumo come down from that jittery, bright plateau. He catches his breath just enough to stammer out another Icha Icha-worthy line or two: "Oh, sempai, please, I want you to come in me, fill me up with it, please—" and that last bit of encouragement is all Kotetsu needs, shuddering all over, his head thrown back as he comes hard.
He keeps it together enough to not just collapse on top of Izumo when he's done, and a good thing, too, because Izumo feels too wrecked to support him. Kotetsu flops down next to Izumo, grinning, and throws an arm over him. Izumo hangs onto the transformation for a little longer, basking in the stretched and sore and shaky feeling, before the effort of holding it doesn't seem worthwhile anymore. He releases the jutsu, feeling the push-snap of returning to himself. The aches fade, better absorbed into his full-grown body than his teenaged one, but he still feels pleasantly worn out.
"You know," Kotetsu says, "for somebody who wanted to be led astray, you turned out to be kind of a handful."
"Mmm," Izumo says. He rolls closer, using Kotetsu's shoulder for a pillow. They're going to want dinner. It can wait. "Must be all those years of you being a bad example."
Kotetsu's laughter is soft, comfortable. "Must be."