Above all, Kei prides himself first and foremost on perception, of his surroundings and most importantly of himself.
He grows up believing with all his heart that to know something is to control it, that you can shape any situation around you if you understand it well enough. From knowledge comes mastery; from Akiteru's intimate knowledge of the court and every position on it comes inevitable victory.
The day he learns differently is the day Kei's mindset moves from realize your environment to realize yourself.
It takes him only a few months for the last vestiges of anger at the Karasuno team to burn away and for the concept taking root in the back of his mind to become its foundation: that the sharp disappointment in his chest when he turns away from Akiteru springs not from his brother's failure to understand the realities of Karasuno's court, but from his brother's failure to understand that, for all his skills, he would never really find a place on it.
Akiteru's strong, but not strong enough to fly with the giants in Karasuno. The sting of this truth fades long before the sting of his brother hiding from it, finding shame in a truth integral to himself rather than accepting it.
Middle school proves rougher than he thought-testing each of his strengths and weaknesses until he knows his absolute limit in every one. Dissecting his own reactions, each and every emotion he experiences, however fleeting.
It's exhausting, more than he thought possible when he set himself to the task, and between introspection and homework and volleyball practice he enters high school alone save for Yamaguchi, who sticks with him despite all the indifference Kei makes a point of displaying. He cares for Yamaguchi, in all truth; analyzing himself has only left Kei even more perceptive towards other people, and Yamaguchi exhibits a level of fierce loyalty Kei can only very selectively experience.
They make the regular lineup for Karasuno, just as Kei knew they would, for all Yamaguchi's fears. Nerves aside, he has the potential to be a powerful pinch server, with good instincts and the drive needed to gain the technical proficiency he hasn't quite reached yet.
Kei's main advantage lies in his height ; if he didn't already know this the appreciative glances the older members send him would make certain of it. This and and tactical efficiency secure him his place as a permanent Karasuno blocker, albeit a physically underwhelming one.
He lacks Asahi's sheer strength or Hinata's enviable stamina, Kageyama's instincts or Nishinoya's agility. He rubs most of the team the wrong way half the time,and spends the other half blending into the background. Kei realizes these things, accepts them as absolute and moves on.
He lets himself enjoy practice for only a few rare moments each day, smirk widening just slightly when he riles up the growingly infamous weird duo.
Kageyama is a delight to watch when he grows upset, an awkward mishmash of who he was and who he wants to be tripping over itself. It's like watching a house, having lost its foundation, trying to rebuild itself from the ground up, and Kei makes a point of provoking him whenever and wherever possible.
Hinata proves only slightly less fun. He's never had the composure Kageyama attempts to maintain, taking a bit of the fun out of flustering him, but his blushing is just amusing and aesthetically pleasing enough to be worth it.
Kei experiences an odd mix of emotions towards the redhead, mostly condescension with a fair portion of envy and the occasional pity.
Pity, because he watches Hinata drive himself to the breaking point again and again for the sake of a dream that will, ultimately, always prove impossible for someone of his height. Envy, because he has the potential for growth in a way Kei has never had. Condescension, because Hinata works every day to break past his own barriers but can't work for more than a second to understand why these barriers exist.
Hinata frustrates him because he changes, lacks the absolutes that Kei uses to define himself and the world around him.
Hinata learns and learns and learns, and the first time he truly thinks in a match Kei barely restrains himself from working his own nails into the tough bed of his palms to the point of bleeding because Hinata shouldn't be capable of this kind of change.
He rolls this over in his mind later, releasing the frustration that he had tucked away so carefully during the game and considering it.
There is no situation that you can understand and predict completely, Kei tells himself, and allows himself to accept that perhaps he underestimated Hinata in more ways than one.
It's weeks later that Hinata turns to him and grins, shoulders heaving from hours of exertion and eyes scarily intent, and a searingly hot stripe of arousal runs from the bottom of Kei's sternum straight to his groin. He shoves at it, feels it sequester itself obligingly away in some small part of his mind, and simply scowls at the boy beside him.
Fury is the emotion that lingers later, fury and a touch of bone-deep fear, cold as ice. The idea that there is some part of him that he could have been so wrong about rakes at his lungs for days after, leaving behind a lingering discomfort that even Yamaguchi picks up on.
He's long since accepted that he favors men, had spent only a single week deliberating over it during middle school before realizing the sheer nuisance that would emerge later from denying so simple a part of himself.
Rather, that Kei could favor Hinata unsettles him, usurps the long-held absolute of how he feels towards him, grudging respect and envy being the closest to admiration he comes rather than outright attraction.
Kei should want to knock Hinata down and laugh, not pin him in place with one arm and watch the shorter boy squirm, and that terrifies him.
It all comes to a head during the training camp; watching everyone around him change, and watching them succeed, even those team members he thought fixed in place. So Kei breathes and thinks, day after day, and recalls something his brother said once:
"What's more important, who you are or who you want to be?"
So he fights back the fear that rises like bile in his throat, what if I fail and all my hope was useless in the end, what if I'm wrong, bites his tongue and asks Coach Ukai for help to become better. A better blocker, better friend, he hopes, and maybe even a better person.
He hates running, has ever since he looked up one day during recess in middle school and realized that no matter how hard he pushed, he'd always be slower than someone else in the class.
Kei hasn't run willingly outside of practice or gym class since that day, but a few weeks from the spring tournament he bruises his knees on the court floor and struggles to get up for exhaustion and thinks, fuck this. He's going to get stronger if it kills him, even if he hates every minute of it, or at the very damn least he's going to try.
He recalls Hinata asking him and Yamaguchi once if either of them were interested in weekend practices, running to the school and back, because Kageyama lived too far away for them to reasonably run together.
They'd both said no at the time, Kei seeing no point and Yamaguchi too busy with serving practice, but the same day he falls he swallows his pride and asks Hinata if the offer's still on the table.
Hinata blinks in surprise and beams at him enthusiastically, if at first with a bit of suspicion. They agree on Saturday morning, at a time just before the sun rises, and Hinata waves at him when he leaves while Kageyama squints at him from the door.
Saturday morning and Kei forces himself up to the sound of Hinata knocking at the front door and heads out with a hasty goodbye to his mother.
He braces himself at the sight of the mountain trail they're taking-Hinata's normal route, the redhead tells him cheerfully as they start upwards-and Kei recognizes the exact moment at which the run starts to hurt, lungs straining and legs burning.
He considers quitting, just briefly, and thinks instead of Asahi and Noya, training day in and day out together to achieve a combo simply because they want to be better. Yamaguchi, walking in most mornings with bags under his eyes and bandages around his hands from late practices. Even Kageyama, breaking down everything he was for the sake of who he will be.
Hinata-Shoyo, he tells him, call him Shoyo-is a constant presence at his side, darting ahead at times before sliding back into place. He's hardly winded, even while Kei wheezes and slows with every step uphill, and urges him on loudly as though they're friends, not just teammates.
"Shut up," Kei tells him weakly, breath choking on the words as he gulps for air. Shoyo simply smiles, telling him keep pushing, just one more, we're almost to the top!
They reach the top with some fanfare, Shoyo near skipping his way to a small ledge off the side of the trail and Kei collapsing onto the grass, sweat dripping from his hair down the sides of his face and onto the ground. His glasses have long since smeared over, and Kei lets out a small nn of resistance when Shoyo tries to pull him up, rambling something about look at the sky and come on, Kei, barely audible over the painful thumping of his heartbeat in his ears.
At some point during their run the sky has lightened, and when Kei grudgingly rolls onto his side he watches the sun rise over the city for the first time in what feels like years, Shoyo sitting beside him with a reluctant whine.
The wind this high up cools the stickiness of Kei's skin satisfyingly, and when he looks over he admires the play of light across Shoyo's face, the long stretches of freckles that run from his cheeks all the way down his short, short forearms.
Not for the first time Kei wants, and for the first time since starting high school he gives in, and pushes himself up just high enough to snag Shoyo by the collar of his t-shirt and kiss him.
It's more than a little gross, Kei too tired to do more than press their mouths together and his skin still slightly slick, breath huffing lightly against Shoyo's lips between kisses. But Kei can feel a warm hum of contentment start up in thorax and lets it grow, until it seems his whole body is full to the brim with joy, and he accepts it, from the deepest to the most shallow part of his mind.
Shoyo's bright red when he pulls away, even the tips of his ears flushed, and Kei can't help the little snort of laughter that slips out when he starts to stammer, pushes himself slowly to his feet and pers off towards where the school should be on the other side.
"Why?", Shoyo eventually manages stutteringly, watching him stretch lazily from his place still on the ground.
Kei shrugs and outright smiles, tilting his head to consider.
"I felt like it," and oh, he can feel the truth behind his own words, for once not tinged with self-loathing or restraint, and he laughs.
"Try and keep up, Shoyo," he says, and turns on his heel and starts running, the slap of too-quick footsteps and flustered yelling quickly following behind.