There's no particular rhyme or reason to falling in love with Itachi - his underaged cousin - but then again, there's no particular reason not to. The age difference isn't too big - or it won't be, Shisui reasons, once they're out of their teens and into the long, ambling summers of their twenties, and probably married. They will spend their senile winters on the beaches of Okinawa, their hair as white as the inviting sands, and Shisui will feed Itachi clementine segments after carefully removing the seeds - perhaps they will keep a summer house tucked away in the lonely, beautiful wilderness of the Isle of Man, to escape the scorching heat - anyway.
Anyway, they're young and fresh and still completely mobile, and Itachi, at least, is very sexy right now, so Shisui doesn't see why they can't have sex. A lot of sex. This is what Romeo & Juliet laws are for, and you're only this good-looking once, right? So there's no harm done, it's just an efficient use of their youth.
He presses a kiss to the milky white junction between Itachi's leg and his erection - Itachi mutters something under his breath, probably along the lines of get on with it, and his fingers twist in Shisui's hair. Which hurts, but Shisui doesn't mind - Itachi isn't very good at getting head, but they have a lifetime to work on that little foible. And Shisui's hair will not be noticeably disturbed - it's not like Itachi's, which is the only hair that Shisui has ever thought might deserve to be called tresses.
"I have class in ten minutes," Itachi hisses at him, cheeks coloring with the suggestion of pink, his trousers down around his knees, but Shisui is a procrastinator; he just grins up at him, continues to nuzzle at the soft skin of Itachi's thighs, breathing damp hot air on Itachi's shaft. This is what he likes about sex: the anticipation, the dragging-it-out. It makes the climax so much more climactic.
They may be in a closet and wasting Itachi's lunch break (Shisui's lunch is an hour later, and technically speaking, he ought to be in class; he ditches U.S. History on such a regular basis that the teacher has forgotten his name) - so unfortunately, Shisui doesn't have the time to set up a rose-petals-and-candle-light production. But he will still savor the tension.
"Relax," he murmurs, and licks, with languid anti-haste, along the underside; Itachi sputters, chokes on an expletive, glares at him.
"This is not foreplay," he whispers, and sounds offended: "this is teasing."
Itachi is a neat, orderly, and efficient person, and if Shisui let him have his way in the bedroom, they would probably fuck for precisely twenty minutes on weekdays at exactly the same time; forty-five minutes on the weekends and holidays, of course, and then maybe on Shisui's birthday they'd go for a whole hour... Shisui imagines Itachi with a stopwatch - no, an egg timer - a metronome -
"Quit bitching," Shisui advises, his pride nettled. "I could always just not blow you, and show up for class instead."
And my, isn't that a glare to remember. Shisui thinks that at some point he will have to make a scrapbook.
"I was kidding, genius," he laughs (he likes to think that he chuckles, but his voice is still too young; it's more of a giggle). "I wouldn't leave you hanging." And he wouldn't, ever, because Shisui is seventeen years old and completely besotted, and holds a really proprietary view of Itachi's hard-ons.
"I know," Itachi says, softly, in that special voice he uses when he thinks Shisui is moronic but still very cute. He caresses Shisui's face with his hand - and then he slips his thumb between Shisui's lips, between his teeth, holding his jaw open, and Shisui would have said something affectionate and disdainful, like 'spoilsport,' but it's kind of difficult to enunciate properly when someone's sliding their dick into your mouth.
He settles for rolling his eyes, and then 'gets on with it', hollowing his cheeks and sucking, head bobbing up and down - carefully avoiding the brush of teeth - clinging with both hands to Itachi's thighs. Itachi tastes faintly sweet - he's vegan, eats a lot of fruit - and salty, when Shisui's tongue manages to wander near the slit at the head. And of course it's Itachi, who is so far beyond hot he makes porn unnecessary, who is probably brilliant enough to skip a few years of high school and head straight for an Ivy league university, who is the perfect eldest son for the head of the family, who is basically doing Shisui a favor whenever he deigns to jizz in Shisui's mouth... It's a good thing Shisui has a few years on him, because if they were the same age, Itachi would be completely overwhelming.
As it stands, Itachi is only mostly overwhelming; and Shisui is a study in arrogance, which shields him from envy.
Shisui breathes heavily through his nose as Itachi (inevitably) speeds up the pace - his parents have begun to suspect that Shisui smokes, his voice gets so rough - he tries to keep sucking, makes a gallant effort not to choke, wraps his fingers around the base of Itachi's dick. Looking up, he realizes that Itachi is staring at him - staring at the slide of his erection past Shisui's reddening lips, a moue of satisfaction winding up the corner of his half-smile, and something clenches in Shisui's heart.
He can feel Itachi's precise, efficient little heartbeat on his tongue, against the roof of his mouth - partly because it's burning a hole in his lungs and partly for theatric effect, Shisui lets himself moan, the noise vibrating into Itachi's dick, and Itachi hisses again.
His fingernails dig into Shisui's shoulders as he comes in pulses - with a sense of immature greed, Shisui gulps all of it down. He's glad he jerked off into a tissue before they started - he hates the feeling of dried jizz in his pants.
"... Thank you, Shisui," Itachi tells him as he pulls out, smirking like someone who's just received a really awesome blow job might be expected to smirk. Shisui scowls at him.
"Yeah, yeah, aren't you suave," he croaks, attempting to get to his feet and dust off his aching knees. This is his least favorite part about sex, particularly janitor-closet blow jobs in the middle of Wednesday classes: the awkward shuffle of the aftermath.
Itachi surprises him by kissing him, then, running his fingers through Shisui's hair again as if to apologize for the earlier yanking, and Shisui's mouth probably still tastes like dick, but Itachi doesn't seem to mind. Shisui relaxes into it, enjoying their height difference now that he's actually on his feet, appreciating the lemonade romance of the moment. Star-crossed lovers, stealing a moment from the world in secrecy, tangling their bodies and their hearts - sweet but beautifully sour.
Abruptly, Itachi breaks off the spontaneous display of affection, returning to his usual unfair composure. "Two minutes until class," he says, pulling up his slacks, buckling his belt, and shouldering his book bag with military precision (and how does he do that, seriously, he doesn't have a watch). Someday, when Itachi is thirty and has acquired the dignity of age, he will not seem so odd in his exactitude. "I will see you after school."
Shisui sighs, shaking his head in fond disgust. However elegant and refined and waifish his jailbait cousin may appear, his temperment is completely unpoetic. Itachi has no tolerance for the contrived. It makes the expression of tender thoughts - things like winter becomes you, beloved, and other half-poems - very difficult for Shisui, who, prior to their whirlwind courtship (they ate lunch together a few times and then Itachi jacked him off in the library and then they were a thing) had considered himself a master architect of bullshit.
"Yeah, see you," he coughs, and savors the sight of Itachi leaving him without so much as a single backward glance.
Someday, he thinks, wearing his petulance like skinny jeans, when they have their own home, he won't have to watch Itachi leave.
He waits for his blush to die down so he can amble into the cafeteria and steal food from - oh, Anko, probably - and speculates on the schoolwork he's been neglecting. ... He remembers, coming down from his post-coital cloud with a sinking feeling, that he ought to be working on college applications. (Shit, Itachi will murder him if he doesn't get them in on time - or worse, stop having sex with him for a few weeks.)
"Damn," he mutters to himself, purely for effect, as he strides out of the broom closet. "Damn."
Itachi is the sort of bewitching muse for whom the creative young man wants to build castles in heaven - pluck pearls from his heart to offer up as baubles - die in Armani on the battlefield of some soul-crushing corporate job to provide financial security. Luckily, Itachi possesses a contemptuous sort of noblesse oblige in regards the creative young man - Shisui, to be specific - and is not the sort of demigod that requires sacrifices. Instead - Shisui thinks idly to himself as he saunters in the general direction of lunch - instead, he and Itachi both make their private sacrifices to the living thing that is their relationship. (That's kind of good - he should write that one down.)
And if relationships were trees, he segues, stretching the idea a little too thin, theirs is still white-birch saplings - delicate, somewhat hardy, to be cared for meticulously - it cannot compare to the densely beautiful vivre of Mikoto and Fugaku's old-growth forest, or the hardy pine groves of the Uzumaki brat's parents. (There's an orange blur that darts around Shisui's peripheral vision when he visits Itachi's home and which occasionally gets its ass whipped by Sasuke.) But they are gardening together: pulling out weeds, grafting together their strengths, sheltering their bond from the elements.
"- Bitch, don't you touch my fries," Anko warns him, and he grins at her, blinking out of his reverie, and takes a fistful. Trees aren't the right metaphor. What's the right poem? Do not go gentle into that good night...
The point is, he concludes, there may not have been a good reason to fall into love with his cousin, but Shisui has collected an arsenal of reasons not to fall out of it.
A/n: pointless fluffy fluff was pointless but ... cute?