A/N: I found this prompt while scrolling through tumblr: an au in which everything is black and white until you see your soulmate. Alternatively, everything will return to black and white when that person dies.
Here's what I came up with.


Sarah still remembered the time she first saw color. It was surprising, to say the least. On a crowded subway, holding onto an overhead strap and listening to the murmur and hum of passenger voices and the wheels on the tracks. She had to turn slightly to make room for new arrivals and, as she faced a bench of seated passengers, it hit her like a baseball bat.

She'd only had colors described to her, and of course that wasn't nearly sufficient to explain what colors actually were. But then suddenly they were there, vivid and lively and all at once and she gasped without meaning to. A split second passed before she realized what it must mean that she was seeing color now, and then she managed to focus on the people before her, trying to pick out the person who had triggered it.

No one was looking at her, so she didn't have any kind of facial cues to go on, couldn't pick out another astonished person whose color had come to them, too. There was an older balding man holding hands with a woman his age. Beside them was a school girl, and next to her was a young woman, about Sarah's age, with dreadlocks and cat-eye glasses. She was engrossed in a magazine that had something that looked like a DNA helix on the cover.

Sarah fixated on her and an inexplicable warmth blossomed in her chest. She took a deep breath, shifting her grip on the holding strap, and reached out to brush her fingers against the woman's shoulder.

"Excuse me," she said.

The woman glanced up at her with eyebrows raised in curiosity, and as she saw Sarah's face she froze. Sarah watched her features register shock, then amazement, and then the broadest grin Sarah had ever seen broke across her face. There was a moment of breathless silence between them.

"Uh, hi. I'm…I'm Cosima Niehaus," the woman finally said, extending her hand with a slowness borne of awe.

"Sarah Manning," Sarah replied, taking Cosima's hand, noting beneath the wonder that whirled in her mind the warmth and softness of Cosima's skin.

As they looked at each other, each trying to fathom the significance of the frozen moment, Sarah suddenly knew that when she told the story of today, the color she would describe most vividly would be the bright, dappled green and brown of Cosima's eyes.

—-

Sarah hated the color red. Hated the way it stained Cosima's pillows, hated how it splattered on the porcelain of the bathroom sink, hated the way it slid into the creases of Cosima's palms. It filled her nightmares whenever she actually fell asleep, which wasn't often; she spent most nights laying awake and watching Cosima's chest rise and fall.

Cosima had gotten worse all the same, the attacks becoming too frequent and too severe for Sarah to help anymore, and Sarah had been forced to check her into the hospital. Sarah hated that place. It was all white and gray, reminding her too much of what the whole world had looked like without Cosima. And it smelled of death.

Sarah had returned home for a shower and to pack a fresh bag of clothes for several more overnight stays at the hospital. She made sure to grab the afghan Cosima's grandmother had knitted for her and Cosima's favorite cardigan. The hospital was never warm enough.

She was walking down the street to the bus when she pulled out her phone. There was missed a call from Cosima. She ignored the blinking voicemail icon and dialed Cosima's number. The line rang three times and then everything — the blue sky, the brown brick buildings, the red fire hydrant, the streets and sidewalks and fences and telephone poles — turned gray.