Fingerprints on Glass
Set two years pre-series. Spoilers including the Chuunin Exams. Inspired by S.

Kabuto learned something when he was very young, before he began his lifetime's infiltration of Konoha. Whatever you touch, you must always put back exactly as you have found it. Leave no marks behind. Memorize the angle of the pen before you make changes. Whenever you clear away objects in front of a cabinet door, do so in the same order that you will replace them afterwards.

Make a game for yourself if you have to. Play until you're perfect. Methodical attention to detail is what empowers spies to move through their worlds like ghosts. They contact everything, but leave no sign of their passing.

No master, Kabuto was taught when he was child enough to still smell like milk, no master really dies until they get tired of covering their tracks.

Kabuto thinks, at seventeen, that he's right at the cusp between being weary and wanting to live forever.

Metal is Kabuto's hardest challenge. That and glass. The natural oils of the human body are identifiers of unique fingertips, which Konoha's police force loves. Prints can be lifted from a variety of objects and used against you later. Your own hands are your worst enemies.

Fingertips are among the most sensitive parts on the human body. Using anything else while searching blind would be like trying to hear with your foot, or taste with your nose. To combat this, some spies slice away the upper layers of their skin, leaving scarred ovals to provide anonymity. This technique unfortunately kills any delicacy of nerves, rendering it limited in usefulness.

Because of this, Kabuto has trained himself to stroke objects with the sides of his fingers. Knuckleprints leave identifying smears, but these are harder to distinguish and match up later. The underside of his wrist is occasionally used, when he has remembered to smear his scent with chemical erasers; the area is an erogenous zone, filled with human pheromones. Kabuto prefers his blank.

The process takes more time as he rolls his knuckles back and forth over objects, stimulating the small hairs of the hand, but Kabuto prefers this method. It teaches him to use every part of his body as a single synchronized tool, and this gives him an edge he hopes no one will expect.

Practice is necessary for Kabuto to retain his sensitivity. He makes impatient gestures that secretly disguise stretches. Rolls of his wrist keep the joints limber. As he flexes his limbs, Kabuto imagines that he is touching everything around him: classroom chalk and the teachers who hold it, the wastebasket and desks and chairs. Invisible water runs over his hands. Tree bark scrapes his arm from a distance. Kabuto caresses the world, and leaves nothingness as a signature of his transgressions.

He's addicted to his craft. He cannot resist an investigation, not while on his Konoha missions or while working in the village hospital. When they bring in three jounin who have been caught in an explosives trap that sprinkled black poison on the air, it's Kabuto's responsibility to provide bone-splints and administer countermeasures to the toxin. Two of the jounin are unremarkable. It is the third, predictably, who catches the teenager's hungry attention.

The third is made of glass.

Hatake Kakashi. The Copy Ninja, who can imitate the cant of your head if he catches you watching, and sometimes even if he doesn't. Hatake. Who is dangerous because what goes into his eyes stays there, and is reflected back later when you least expect it. Who can turn your secrets against yourself, become your mirror image.

Mirrors are only glass, Kabuto reminds himself, even as he fills a syringe from a vial of antivenom, careful to hold the bottle by the label and his knuckles. Glass, with the backs painted over so that light is trapped when it tries to enter. Mirrors swallow everything, and they remember it in their unbreachable depths.

This is not the first time that Kabuto has looked upon his pale-headed twin. Orochimaru has spoken frequently about the teenager's resemblance to the Copy Ninja--mostly in regards to talent, but also occasionally, defiance. Hatake Kakashi, who learned how to bind one of the Sannin's Curse Seals. Whose face is slashed in a threadworm scar that occurred in a story Orochimaru never relates, and which Kabuto thinks about at night when he touches his own unmarred cheek.

One of Kabuto's biggest problems when he writes is that he prints the characters out of order when he's distracted. His parents had originally feared this as a sign of a learning disability, a condition that would later develop into full-blown neurosis. Kabuto hastily explained his carelessness once his father started to pull out the measuring pinchers for a human skull, the long metal lines resembling the arms of a monstrous praying mantis.

Despite that, he wanders back to the practice. When he picks up Kakashi's medical chart from the foot of the bed, Kabuto scribbles the administered dosage in reverse. 10 ccs becomes 01. Another nine ccs delivered by a medic who sought to repair Kabuto's mistake would overstimulate Kakashi's nervous system and leave the man in convulsions; the brain damage might be reversed if they caught it in time. Twenty percent chance. More than fair.

Kabuto debates the value of Hatake's death, and then goes back and corrects his own numbers.

Sometimes Kabuto worries about arrogance while he handles the medical records of Konoha and estimates how many patients he could kill in a single night's idle work. Confidence, he knows, is a bad rule. It's when a spy becomes either so deluded or so desperate that they weave falsifications more and more wildly, take risks that no one can win. They create impossibilities that are deliberately transparent, desiring nothing more than to be stopped so that their falsifications can finally end.

If the Copy Ninja lives by the reflection of others, then Kabuto wonders if Hatake also waits for the day he will be broken.

Kabuto has thought about exterminating his clone and eliminating at least one genius from out of Orochimaru's register. The Sannin has so very few that he can reach, after all. Kimimaro is already dying, and Sasuke is too young to demonstrate quality potential. Kakashi--Orochimaru would not possess Hatake's body at this stage of affairs, even with the Sharingan eye, but Kabuto doesn't like the fact that the option's there.

Pros. Cons. Kabuto progresses along Kakashi's hospital bed as he tries to decide which side is heavier. One of his hands reaches out, tracing the contours of Kakashi's feet, twin mounds sticking out from underneath the flimsy cotton sheet. The backs of his knuckles slide along Kakashi's inner thigh, seeking out the femoral arteries and resting above each in turn. Ten seconds would gutter out Hatake's veins after one judicious slash; five if both were opened at once.

Left to right. The two ninjas are separated by a cloth so thin that Kabuto can feel the threads of Kakashi's boxers through it, stitch by stitch. His fingers move along the muscles. Shins, knees, thighs. Hips. Stomach. Kabuto slides his hand across each in turn, exactingly patient until he has memorized a three-dimensional picture of Hatake, and can reproduce the man's body by shaping wet clay in the dark.

The sheet is folded at Kakashi's waist. Both of the jounin's hands rest atop it, docile beasts of murder sleeping at his sides. They are scarred with pale nicks, veterans of dozens of missions. One thick line bisects the back of Kakashi's right hand, a wound that Kabuto knows comes from a shinobi's willingness to impale their own palm on an opponent's weapon in order to turn it aside.

Finally he arrives at the head of the cot and looks down upon the unconscious Copy.

Even in a hospital ward, Kakashi keeps his mask on. The dark shape settles over Hatake's features like a squatting pool of black ichor. It licks over his nostrils. The nurses who had swapped Hatake into the bed hadn't removed the facial covering, leaving it behind as a curiosity, even while they had absconded with his shirt and pants.

In his thoughts, Kabuto knows he can handle the mask and replace it with no one the wiser. He's become a master over the years. Already he is memorizing exactly how the fabric falls over Kakashi's face, picking out the slimmest wrinkle and engraving it to mental stone so he can reproduce it later.

Studying Kakashi's unconscious body, Kabuto finds himself debating if this is the right opportunity to risk learning more about his informal rival.

Mirrors are glass, the spy thinks. Just glass.

With that in mind, Kabuto reaches out to stroke the surface of the face protector with the back of his knuckles. He wonders what Kakashi's bare chin will feel like, or how the underside of his jaw might taste.

He'd like to know, so he won't have to ask Orochimaru how similar they actually are.

Just when Kabuto has pulled the fabric down past the tip of Kakashi's nose, both of the Copy Ninja's eyes flare open. One of his hands--the left one, with the IV cords studding the tendons in some kind of plastic loom-weave--lashes up and snatches Kabuto's wrist. The mask snaps back into place. Elastic crawls up Kakashi's face, swallowing it back down.

In the low lights of the hospital ward, Hatake's Sharingan eye is a volcano of blood.

"Who are you?"

Struck dumb for a moment as he sees the resemblance between his own treacherously red eyes and that of Kakashi's, Kabuto only stammers. "I'm the Yakushi's boy." Trapped, panicked, all he can think of are endless rooms of lights flaring on while the filing cabinets are still open, catching him in the act. He repeats out of blind fear. "The Yakushi's boy. Kabuto Yakushi."

Kakashi's hand tightens, grinding bones inside its grip.

Kabuto's fingers are instantly nerveless.

"I was checking on your condition." Excuses pour out of Kabuto's mouth in a torrent. "My parents put me on the night shift, and I'm not familiar with this kind of poison--I'm not very good," he tacks on, sacrificing dignity like a lizard's severed tail. "I wanted to see if you were having a... bad reaction to the antivenom." Bad reaction. How imprecise. Unscientific. How long was Hatake awake?

White brows furrow. "The Yakushi's child?" Kakashi's voice sounds like a bear discovering it has gravel instead of teeth.

"Yes." Groping for his wits, Kabuto works through self-beration. How sloppy of him, to be surprised. A momentary lapse. It will pass, he tells himself, and then states aloud, "I didn't think you were breathing."

But as soon as he says this, Kabuto notices the way that Kakashi's chest is fluttering. The jounin's lungs are distressed. The rest of Hatake's body is not startled, not upset or afraid. Kakashi is still groggy from the drugs that have been introduced to his system. It's proven in the way his movements are sluggish, his voice is slurred; only one of Kakashi's mismatched pupils successfully focuses on Kabuto as it tracks the spy's movements.

Kakashi's breath pulls shallow anyway, trembles of muscle expecting to fight or to flee. Puzzled, Kabuto analyzes the riddle gingerly before he understands what exactly is happening.

The Copy Ninja's lungs are imitating Kabuto's own.

The Sharingan blaze--uniquely lethal to any spy because it can capture nuances of movement and play them back later, like a video camera carried in the head--is unconsciously recording Kabuto.

Upon realizing this, Kabuto stops breathing.

So does Kakashi.

The room is instantly hushed. Kabuto is frozen in Kakashi's grip. Kakashi is immobile in his own mimicry. Far away, the slippers of the hospital staff murmur up and down the halls, ignorant of the confrontation.

It takes very little effort to remove a human's eye. Even, perhaps, that of a Copy Ninja. Kabuto knows just the right angle and the amount of pressure required for the average human male aged twenty-to-thirty, just as he knows the angle of penetration alongside the tear ducts to perform an emergency lobotomy with a chakra scalpel.

But he needs both hands free in order to use the jutsu. Slow, Kabuto tries to take a step away, but Kakashi's hand instantly tightens around the teenager's wrist. It locks into place, and Kabuto watches in disoriented fascination as his own veins start to bulge from the pressure.

It hurts. In order to concentrate, Kabuto counts off--in order--how many bones are in his hand, the average force needed to snap them, and the amount of recovery time appropriate to heal the damage without looking suspiciously capable of doing so. He feels better when he has finished the list.

His breathing steadies before he remembers to keep it rapid, nervous, the lie of an eternal genin. It is not too late to wipe his fingerprints away.

"I didn't mean to wake you," Kabuto claims, honest.

"I'll be gone before you know it."

"It'll be like I was never here."

Eventually Kakashi releases Kabuto's hand. "Good," the Copy Ninja grunts, but Kabuto can see the way that Hatake's eyes are both tracking him, swallowing him down into their mirror's void-depths as Kabuto backs away, watching his inverted reflection grow smaller until he retreats entirely.

Kakashi's body heat lingers on Kabuto's skin. Later that night, when he's listening to his parents discuss the use of adrenaline during heart attacks, Kabuto soaks a washcloth in the kitchen sink and scrubs his wrist. Hard. He works the area until it's raw and protesting, red pinpoints of broken blood vessels rising in protest to the rough damage.

Even so, Kabuto can still feel the oils of Hatake's fingers staining him all through the night.