There is darkness, and there is light. Golden, thick, giving shapes an allure they would not normally possess. A beautiful optical illusion. Nothing more.

Breathe.

I cannot see every wrinkle on his forehead, only the important, most prominent grooves that sit above his eyebrows. I remember the other wrinkles, so I fill them in. The scars too, they matter, and the freckles that I can only see under the light of Bart's. I cannot see the colour of his eyes. Here, they swallow the light, and the darkness too.

Good and bad. Doctor, soldier.

The shadows that line his smile are the same as the one that lined his grimaces before, in the long beaten path around the back of the warehouse. 'We're heading right into their fire,' he growled.

He was right, of course, and we danced between the bullets as we ran as fast as we could into the belly of the beast. Always running into danger. Adrenaline is a wonderful silencer of thoughts, and when the incandescent crashing increases to its peak, there is nothing like it to give me peace. Paradoxical, perhaps, to find peace in war, but why else would humans seek it so often? Why would a doctor go to war? He knows it as well as I do. It is imprinted deep in his bones, beneath the knotted, rising flesh of his bullet wound, where the bone holds the scrape marks, the shatter line, the memory of breaking and bleeding into foreign sand. He knows that the dance we lead is one he can never forget.

.

'Do you do stupid things to prove you're clever?' he asked me once, cleaning a knife wound on my arm. His jaw was tight. His hands were steady. They had not been so steady for weeks.

Displeasure. Disappointment. Not a hero, thought I was, thought I was his hero. Flawed thinking. Wishful thinking. Wishful? Why? Arousal. Adrenaline wearing off. Tired. He is tired. Tired of me. Doesn't want me. No one does.

'That's not the only reason,' I responded quietly. My mind was shouting, but three years spent whispering and becoming a shadow of an idea meant that shouting had been deleted from my surface mannerisms. Facial expressions were not a necessity when dealing with those I would not meet again. There were never emotions involved with them.

But to see John's face, to feel his fist crash into my cheek, to have him swear and then try to treat my bruise instantaneously, forced emotions into being.

Not forgiven. Don't ask for forgiveness from those that will not award it. Don't deserve it.

For God's sake, man, don't drivel.

John's hand settled on my back. This was his skin, rough and calloused, against mine. More emotions came. I could not catalogue them, cascading in a mess. My mind used to be clear around him, but that effect seems to have been rendered moot. Too much time has allowed me to linger over the minute details and draw hypotheses from insufficient data, to draw conclusions before the experiment has begun. We had no time for experiments. My blood was on his hands, coating under his fingernails. My DNA, imprinted under the very hands that were used to heal and injure simultaneously.

'You did it for me,' he muttered, 'didn't you? That jump? Dying?' His voice broke. His fingernails dug into the skin of my back.

Physical pain in exchange for emotional pain. Efficient bargain. Investigate motives for self-injury. Possible links to cocaine. Experimentation possible, if avoid Lestrade and disappoint John. Experimentation not possible. Cannot hurt John.

Cannot.

The answer to his question was not simple, however it seemed appropriate to offer a simplified answer. He did not want to hear my voice. When I had angered him before, he preferred to walk away so that he might not have to hear my voice or see my face. His duties as a doctor prevented him now, but if I kept silent, perhaps I would lessen the levels of irritation.

I nodded, and John sighed. It was the sigh he reserved when I was being inconveniently troublesome, and had placed one of my experiments in the wrong compartment of the fridge. Consequently, he would return to his usual demeanour and I would thereby be forgiven.

.

A car rushes by. Brighter light refracting through the glass, slowed by the curtain, drifts across his face and shoulders. Liquid silver. Alien, on his body, when his muscles move in quick, efficient bursts. The army still lives in his blood, whispering commands in his ear. He still whispers commands in his sleep.

Get behind me.

The light gives the impression that he is moving towards me in the dark, closing the space that stretches between our bodies and our hearts. I tried to forcibly remove my organ from my chest, but it displaced itself into the good doctor's hands. He returned it to me in doses of tea and buttered scones. There is no more tea, no more buttered scones. In their stead, I am offered knife wounds and the sharp smell of hydrogen peroxide sizzling in my flesh.

This is the battlefield. If it heals him, I will become the battlefield.

Deeper grooves around his mouth, under his eyes. He tried to get drunk with Stamford last night – the stain of alcohol still marks the edge of his shoe, the faint scent of Stamford's cologne on his collar – but the effort of keeping quiet about my return got too much. He does not like to lie. His mouth twitches slightly when he does it, so he hides it by running his tongue against his lower lip.

A single scar on his right jaw in the shape of a marriage ring, approximately two years according to colouration and texture. A left-handed man, possibly a stranger due to the obligations a married man would have to his image. More likely a man due to the weight pressed on the jaw to leave a scar. No stitches. What was the fight about?

He leans forwards, hands slipping over the couch. The fabric bends under his fingertips. The blood is still crusted there under his fingernails. It's been a week. He could have removed them if he wanted. Maybe he forgot. Maybe he needs them there as a reminder that I am real. The folds of his shirt cup the darkness. The line of his body gasps in light.

A beautiful optical illusion. Beautiful.

His tongue darts against his lower lip. His jaw tenses, and the rest of his face is in shadow. He shot a man for me, once. He broke a man's legs because they tried to stab me in the neck.

Motions of sentiment. Of fondness. Protection. Soldier. My soldier.

His hand lifts off the couch. I am imprisoned in the silence that I have woven around myself. I do not need to exist in the world of people and normal, social interactions. These are the characteristics I cast aside when I became dead. I do not need a voice with which I can converse, for the memories in my palace suffice for human contact. In truth, I do not need human contact. All I need is him.

The back of his knuckles ripple as his hand draws close. The scars there are so numbered that they have become a mesh of fading lines. The most prominent is near his forefinger, short and fat, due to scraping against a rough surface, such as a wall. Self-inflicted, then. Seven years in age. Something during the war, then, something that made him so enraged that he felt the desire to dull the emotion through physical pain. The soldier has felt a lot of pain. The doctor has lost a lot. He has blood on his hands, too much blood to be cleansed by simple motions of happiness and stains of tea in the carpet.

His hand rests on my cheek. If he could feel the things I feel, he would know the bones there have been realigned slightly. Two years ago, a woman deposited a roundhouse kick onto my jaw. The damage was minimised due to a slackening of her leg and a minimal amount of evasive action on my part, however I had my head bandaged for a week. But he knows the changes were elsewhere.

John knows every compartment of me, or even if he does not, he is aware of the deeper components of my change. He knows enough to rise from his seat, to loom over me so that I might not escape, to move his thumb in the pattern one would use to brush away tears. I am not crying. I have learnt not to do that. The chemical components of tears are easily analysed to demonstrate whether or not a certain individual has been present in a certain environment. My last tears were given to him, when I stood on a roof and prayed that I would have enough courage to jump. In my quiet shell, the demonstration I offer is an impassive face and staring eyes. My body is a cage. My pulse elevates. My pupils dilate. Nothing else moves.

John's body is warm, almost aflame.

I will burn the heart out of you.

His other hand cradles the back of my neck. He should feel that, the scar that comes down from my ear. The light scratches across his face as his mouth twists and his eyes narrow. My pain, not his, and yet he is so affected. He knows the anatomy and the basic architecture of the human nervous system. He should know that this is not the most sensitive place, and yet he is in more agony than I can bear. It burns in my body, over the hollow that should hold my heart.

I have been reliably informed that I don't have one.

His face shifts too far into the dark, where the light cannot reach him. Here, there is no doctor, no healer, only the injured and the murderer, the soldier and the brutal attack. His breath moves across my face, dusting from left to right, down the cheek. He smells like dinner – oil, glass noodles, mushrooms, monosodium glutamate – and his aftershave, and the deeper pheromones that belong to him alone. His lips are chapped. He does not drink enough, and his habit of running his tongue over his lips does not aid the situation.

But his mouth is warm and moist, and his tongue sweeps in. He holds me like we are drowning. My hands hurt. Ah. His shirt is rough, and I am clenching it too hard. But we are drowning in a vast expanse, and the hole in the middle of our universes is collapsing in on itself, and therefore we must contract together to form one being. It is the only possible solution.

But we both know that's not quite true.

His teeth against my skin draws blood. Pain to alleviate pain. I understand this now. We can only exist in the dark, if we are only able to injure each other, but I am informed that this is the natural state of lovers. I would not dare believe that we are lovers, but John's hands believe so. They tell me he is aroused, in all psychological aspects. He wishes to kill me. He wishes to run as far as he can. He wishes he could tell me everything in every frantic breath he takes. He wishes he could kiss the blood out of me.

His hand tugs at my hair. I tug at his shirt.

'I love you,' he whispers against my teeth.

Here is your heart.

I am encased in silence.

'I am in love with you,' he gasps, 'you bloody git, and you ruined me. Do you know that? You ruined me.'

I close my eyes.

And you should never let it rule.

And breathe.

Breathing's boring.

And open my eyes. My doctor is in the darkness because he belongs with me. Here is where we make our last stand, in the silence, in the shadows, where the light cannot reach.

Always running into danger.

I feel his face with my hand, the scars, the lines, the days and the nights etched into patterns. He is a world encased in physical properties, and it is the most fascinating thing I have ever experienced. He is weeping into my palm. If I could have saved him somehow from me, I would have. I tried to, but I couldn't stay away.

And you cannot forcibly remove a vital organ from your ribcage.

'I've always loved you,' I whisper to the dark.

Ah, breathing. Breathing's boring.