Sherlock stands beneath a silver sky and peers up at the silver leaves and beyond to the white moon, who is already sick and pale with grief. The silver is murky with cloud, and snow falls, scatters. Flecks his greatcoat like white paint which brings him back to painting the spare room with John and flicking paint around, white gathering in puddles in the floor not dissimilar to rain. the floor was laminate, too, and in the snow Sherlock thinks about what it would be to make love to John with his ice skates on and turn the floor to toothpicks.

He thinks, out of everything, the infinity of what he's come to know, that birthdays are silly. Time stops for no man, and every second is a whisper wasted, a breath taken from his lungs. Each screaming that he's an endless man. The thought of age, it takes him to growing old, which he doesn't mind at all, but only for John. He'll happily fade with John, watch as nature erases them both, will follow him into the shadows when time's wick is black.

And he doesn't mind, he doesn't care, for time's just wasting beauty, every cigarette will end up in a mother's lungs, every flame will burn down something beautiful. John's frame will eventually turn to dust. It's not the time for death, a breath of life has slipped from John's mouth into his as they slept, a strange sort of kiss.

He looks at the frozen water, lit like a silk ribbon, and his reflection catches. A thousand different versions of this endless man, as sure as he has eyes. The sky is heavy and gravity will pull it down, air tastes like high-pressure-and-ice. Sherlock thrusts his hands into his pockets and watches his breath that forms smoke in the air, lingers like a ghostly companion.

The slice of metal on ice, neat, clinic, vicious, catches Sherlock's ears. In the calm ocean of white that surrounds this tiny man, snow continues to fall. John's in the distance, a few centimetres tall but to Sherlock he's enormous, he's everything and Sherlock moves over, unsure of his legs. Thoughts medicate the distance, but they don't solve. Sherlock's done with thinking, guessing, calculating. He wants to kiss John with his hands bound around John's voice.

Wants to leave the skates and the snow outside, march their bodies across the ceiling and confuse the neighbours.

But settles on a smile, whose worth is unmeasured by currency, not restricted by the trades of men. Off in the distance, the clock chimes, fills the silence with a yellow sort of sound. It's midnight, and Sherlock doesn't care for moments or minutes. They're infinite, they're limitless and high above the stars, deep in the silver.

"Happy birthday," John says.

"Ugh, birthdays," Sherlock cannot sound anything but giddy, but he's human, damned to be desperate for another person. "Off with their heads." The words are aligned perfectly to make John sort-of laugh and shake his head, all warm because they're so fond and familiar, it should be boring but it's not, Sherlock could light fires with the realness of his joy, of his smile.

"Make a wish," To want is to suffer. Sherlock is endless, beyond suffering because even if the snow stops and London is burnt to a crisp, even if they come for his eyes he's got John, and John is everything and more, he's perfect and precious.

"Whatever for?" And John knows, he always knows, can see it in Sherlock's eyes, blue as mercy, green as cool summer water and bright as his bones, their bones, when they'll be found like the lovers of Valdaro. Skeletons entwined, long gone but still even more alive, because believers never die.

Sherlock thinks.

"To die by your side." He settles, too morbid to be romantic but somehow the most beautiful version of himself yet. John laughs again.

"I got you a book. They were fresh out of 'death by my side'," Sherlock's had plenty of gifts before, plenty of kind gestures and birthdays but he's unsure why it means so much. Sentiment is dangerous, is like fire and he allows it to burn in his blood to stop his heart from ever freezing.

It's crudely-wrapped and small, John watches on looking pleased and smug and boundless and Sebastian Wilkes can go hang because he's Sherlock Holmes and he's been betrayed by his bones, carries his love to John by his feet. Is madly, deeply, incontestably and rapturously besotted with an unassuming doctor. His unassuming doctor.

The pages smell like a forest fire. He scans the title. 'The solar system'.

There's time, he knows, to study every star and sun and black hole and neutron star, every nebula and supernova. He's an endless man with John.