It was cloudy and raining; Mycroft has once again offered a knighthood; Sherlock rejected it with a tedious remark; there's another tea stain on the carpet, and 221B smells of aging books and moldy wood again; in short, a perfectly ordinary day in London. It was the afternoon after the case of the Marlborough professor/double agent. The elder Holmes phoned Sherlock to investigate how on Earth are the Germans receiving Intel on the PM and his cabinet's decisions about the EU Debt Crisis before the press releases. All very hush hush, as per usual.
Long story short, the mathematics professor encoded the information using a map of the Asia Pacific and high school trigonometry. Brilliant really, John commented once and Sherlock grudgingly agreed (though he would never voice it out loud), nobody would've thought a top tier educator would stoop down to the basics. The turn coat was caught and, the government (Mycroft) could breathe again. Equilibrium in English society is once again restored.
It goes without guessing that Sherlock is a math prodigy. He's been called precocious to unbelievable, among other things. So, it shouldn't be a shock that exactly 18 hours and 23 minutes after the case, he was still toying with equations in his head.
'But that would mean the 23rd variable is in complete disagreement with the 4th coefficient, rendering the current 57th possible solution wrong.' Sherlock calculated, piercing the innocent kettle with a stormy green gaze. 'That means 9 other solutions are negligible. I'm terribly thirsty. Did John put the kettle on? No. John is still sleeping. Snores in a curious geometric pattern. Only happens when a case is successful'
John, unsurprisingly, has been solved by Sherlock quite a long time ago. 7 days and 13.96 seconds after the Belgravia affair. If John was math, he'd be algebra – the elementary kind, of course; college math is full of condescension and grey hair. The doctor was algebra because his graph had too many Xs and Ys. There were the absolutely undeniable coefficients such as the time he spent in Afghanistan, the years it took to graduate with a medical degree, the PTSD and shoulder wound, how many extra bullets he keeps hidden under the floorboard eight steps from his bed, the number of times he drinks tea in a week over the trips he takes to Tesco's monthly, the exact blue of his eyes, how many times he glances in Sherlock's direction when he thinks the detective isn't looking, and how much sugar he takes (which is none, so the digit is negligible, but nice all the same).
Then there are the shady variables which should be all too clear, but are not like why John shot the cabbie, would he really have taken the bullet the time he had Moriarty in a headlock, why he skimps out on whole milk and buys 2% low fat -Sherlock's favorite, why he keeps on ordering at the Chinese restaurant Sherlock likes when he complained the food was far too greasy, why he would leave any girl in a blink every time he receives a text from a certain Blackberry, why he treats Frankentsein-esque experiments like harmless lab rats at a word from the younger Holmes, why he only uses the expensive fabric conditioner on Sherlock's shirts and not his own, why he is kind towards such dull people, how can he bear to talk to Mycroft for more than ten seconds, why he still stays with Sherlock despite the petulant whining, the bored gun shooting, the inconsiderate violin playing and so many other queer whys, woulds, and reallys that the 26 letter English alphabet would have to be repeated thrice to cover all of them.
By the third time Sherlock was calculating the exact slope, he had to admit maybe John was not completely logical; a quadratic equation that always spews the wrong squares, a wonky parabola with its positives all over the plane. For days, Sherlock attempted to deduce the mickey out of John, staring at him for hours on end; it didn't matter where: at 221B, at New Scotland Yard, at a crime scene, at St. Barts. The watching became so incessant (4th day: 93rd hour: 7th try) that John decided, against all endowed instincts, to ask Sherlock about it.
'Is there anything wrong, Sherlock?' John asked, reluctantly looking away from the computer screen –though he was only using it in an effort to ignore the stranger-than-usual Holmes. 'Are you bored?'
'Dwells on my name 0.435 seconds longer than anyone else. More or less 47 percent of hair is predominantly blond. Smiles in a very concerned way, as if my ennui demands all his attention. Second finger on the left hand twitches involuntarily on knee. John has such lovely knees.'
"No" Sherlock drawled, upper lip quirked as if hiding the most important secret in the world "As a matter of fact, I am very much entertained"
It was on the last day that Sherlock finally had his answer. He was absentmindedly plucking on the strings of his Stradivarius when the solution came to him. In the overwhelming emotion of it all, he had pulled too hard, and a string snapped; it was as if the greatest crime scene in the world was suddenly wrapped in a bow and delivered by Anderson on his doormat wearing a violent pink wedding dress.
Sherlock realized that he loved John. It was the missing variable in the mess he created. It was so achingly simple and profound that Sherlock had to sit down else his heart would destroy his ribs. Love is only true if ex-army doctor owns an absurd amount of jumpers and is undeniably head over heels for high-functioning consulting detective; therefore John is equal to Love; Love is Sherlock's heart. If John is Sherlock's heart then he is undoubtedly the blood that caresses the detective's insides, the oxygen that breathes life into the man, the sole reason for why there is still a Sherlock Holmes.
John Hamish Watson is algebra, calculus, geometry, and just a little bit of biology. He is everything, and for him, the eccentric sociopath would do anything. Sherlock would forcefully divide the entire universe by zero for John until parallel lines are no longer parallel, imaginary numbers become counting numbers, and right triangles go from 90 degrees to 93.
John is his domain, Sherlock's infinity with no negatives.
"Sherlock? Is that you?" John entered the kitchen, eyes slightly droopy from sleep. "Do you fancy a cuppa or maybe a bite of –?"
The androgynous genius rushed to John, all truffle curls with insistent hands, and kissed him softly on the mouth.
'Exponential' Sherlock concluded.
A/N: I do not own Sherlock Holmes (and his John Watson).
A/N: Thank you for reading! Reviews are greatly appreciated!