Shikamaru suffers from a unique brand of synaesthesia.

It is not a congenital condition; of this he is sure. When he was young, his mind would process subjective information with a clarity and straightforwardness that he envies and misses. A person was a person, an apple was an apple, and a singing bird was a singing bird.

He doesn't remember when this mangling of his senses began. It might have been around the time he was introduced to math. Or when his father taught him the rules for shogi. Or when he had gotten a detailed explanation of the inner workings of a clock, once long ago. He knows it started happening sometime around when his curiosity kicked in to feed his voracious mind.

Shikamaru likes learning. He is constantly reading, learning, and evaluating. He cross-references what he knows, draws links, posits hypotheses on every breath. He's long been acquainted with this integration of facts, the assembly of small parts into greater wholes, greater truths. It's who he is, and if he could be bothered, he would commit the entirety of his deductions to paper. He doesn't because it could well occupy the rest of his life and he hates school and the endless circular rambling of academia.

He wishes, however, that the rest of his brain wouldn't follow suit and interlace every last sensation.

It's not confusing, per se. If it were, he suspects he would be functionally useless. When he sees, he still sees as he always has. The exception is in his mind, in the associations it submits to whatever sub-organ coordinates his various mental inputs. He blames his parietal, occipital and amygdala, but there are a few other regions on the list sharing responsibility.

The usual analogy of layered sensations doesn't really apply, and he has done enough research on the topic to know he is something of a unique case. The best analogy that he has come up with is that he has two minds interacting in one skull. One of them, the one he is most used to, is normal, and the other likes attaching completely inappropriate non sequiturs to the things he experiences from day to day.

The first time he noticed it for sure was after his first day at the ninja academy. He had, in the course of student introductions, become aware that many of them were already dangerous individuals, and really all of them were there for the express purpose of become even more dangerous. All of a sudden he had become aware of colours, stretching out over spaces surrounding each person, threat zones made manifest in his mind. The colours were assigned specific roles, too. An intensely orange aura had glowed into life around Kiba when he noticed how much sharper dog-boy's nails were. A brilliant red cone had appeared in front of that stoic prick Sasuke when he overheard some girls gossiping that he could breathe fire. Chouji's family was well known to his own, but he'd never noticed the green expanse around his friend that darkened at the edges -- his mind had figured out Chouji's threat level expands when he has room to accelerate.

The next time he had sat down to play shogi, his pieces had developed similar auras, similar projections of force that interlocked and expanded, shifting with every move he or his opponent had made.

His condition is much worse these days.

His mother's grilled mackerel, a rare treat with a complex salty-sweet flavour and a rough texture enhanced with a dash of lemon, is now associated in his mind with the most perfect of equations -- e raised to the power of i by pi and one is zero. He despises boiled eggs because he can't eat them without thinking of low exponents of two, which are boring as all hell for the most part.

It works inversely, too. Smells dictate importance or interest. Bookstores smell like mackerel, and chores smell like old eggs, sulfurous and fetid. Even the mere notion is enough to render the smells in his head.

The more he learns, the more he experiences, the more he is affected. Every time Ino travels into another person's mind or Asuma lights up a cigarette, he can hear a whisper that grows into a keening wail, a siren that peaks just before Ino needs to leave or the cigarette is short enough to burn Asuma's fingers. When he gets an idea, he actually hears a click, as though his brain were a steam-age machine with cogs that fitted into place and punched out solutions.

When he cries, he can feel his bones breaking. When he laughs, he can taste potato chips. When he thinks, his hands tingle. When he wins, his skin prickles, and when he loses it burns.

Some days he can't stand it, and he does his best to escape. In his dreams, he is free from this agonizing interference, and when he stares at the sky, he sees no additional colours because there is no strategic or tactical value in the clouds.

He wants nothing more than to be average.

The first time he met Temari, his brain had made several assumptions. She had a fan, so her aura had immediately been assigned a pale blue, an aura that extended in great swathes away from her. She had been tough looking and harsh, and when she had demolished Tenten in the preliminaries, the blue had darkened considerably.

He'd lost to her in the final part of the exam, but as he had held his hand up to concede, his remembers he could feel neither the typical prickle nor the rare burn. It had been new, something to relish and remember, a return to the normality he has craved for so long. In that moment, that long, languid moment when he had stretched their arms skyward and she had trembled and braced herself even though she had been seconds away from winning, Shikamaru had felt nothing.

Her aura had disappeared because she'd been trapped, and for some reason there had been no distractions, just him and her, in the bottom of the arena.

He hadn't had the chance to see her again for some time after that.

But she had showed up to save his ass in the forest when they were out getting ruined for a traitor's sake. He had half expected her to harangue and needle him all the way back to Konoha, but she didn't. He had definitely expected her to give him grief while he worried about his friends -- and damn hot needles that shoved under his skin, and the screech of crows that accompanied it, and the smell of melting flesh still fresh from the Sound bitch's illusions -- but she didn't.

He hadn't realized that her aura had completely disappeared in the hospital while she had talked to him and comforted him in her strange way until a few days later.

Today, he notices. He notices how his brain stops making all those bloody ticking sounds when she talks, how she is the only person in the entire world whose colour-coded threat range disappears when she faces him. How she smells uniquely of her and not like something else that he likes. He knows now what peace feels like, and it feels like her lips. He knows that it infuriates her when he smirks while she's chewing him out, but he can't help it -- he smirks because she's all he can hear.

When she has to go, he misses her. When he misses her, her smell springs into his second mind, subtle and sweet, hot sand and cactus flowers, like the taste of mackerel on his tongue and the complexity of phi.

Every now and then he wonders if synaesthesia is as bad as it always has been.