Summary: An early encounter between the Doctor, Sarah, and the Reapers leaves the Doctor forever changed – but everything in life is a tradeoff. AU but could almost fit into canon. Based off of tekiclutch's art at the LJ community 500yeardiary, (FFN won't allow the link, it appears) and various comments that they resembled Reapers' wings. Look at the art first, really. Bookended before and after by an AU version of the events in Father's Day, epilogued by a missing scene from School Reunion. Yep, hittin all the cliches, that's me.
Characters: Bit of Nine and Rose and co, a lot of Four and Sarah, and then a little Ten and grownup!Sarah. Not meant to be shippy, so please don't take it that way - when a friend hurts, you're there for them, and that's a kind of love all its own.
Spoilers: Father's Day AU, School Reunion. Beyond spoilers, it really HELPS if you've seen Father's Day or at least know what Reapers are/do.
Rating: Hm. Some pretty bloody imagery, might be a swear or two sprinkled in. PG-13?
Disclaimer: None of these characters belong to me. Obviously.
Misc notes: Longest fic I've ever written, and I'm not 100 satisfied with every single word – seems I only really stay completely on form when I'm doing short one-chapter one-shots – but I like the motion of it, and the continuity. Which are the same thing, after all, just in different dimensions.

tradeoffs

chapter one: dark mirror

"Everyone, behind me!"

There was fear in the order, underlying the determination. Fear was not something Rose would ever get used to hearing from him – wouldn't likely get the chance to, either, now that the black, deadly creature had materialized inside the church. Her fault, again. How many times had it been her fault, in the last ten hours? The Doctor stood between the huddled group and the Reaper, hands crossed over his chest and gripping at his upper arms, face tight with concentration and strain. "I'm the oldest thing in here!" he shouted, and it was ominous, and it was brilliant and dark and dangerous, but it was just words, and these creatures would never bend to words. The Reaper spread its wings with a scream and dove towards them.

And, as if through a mirror, another pair of the black, taloned wings whipped open barely inches in front of Rose's face, shiny with something that, in this instant, she was sure was blood. And they were attached to her brilliant and dark and dangerous friend, now hunched forward in obvious pain, head snapped high to hold eye contact with the beast hovering now just a few feet away from the group. Looming.

The universe held its breath.

Voice scraping and twitching out its frustration, the Reaper whirled away from them and shot instead for the front of the church, straight towards the TARDIS where it still struggled to rematerialize, gold light glistening around its lines and corners, holding so much promise. Easier prey. Hope was the simplest thing to kill.

"No!" shouted the Doctor, stumbling forwards after it, but before he'd even taken a proper step the Reaper had collided with its target, evaporating with it into nothing. No more hope. No more chances. The key dropped onto the carpeted step, and with it went the Doctor, strings cut, tumbling bonelessly to the floor in bloody heap of man and something not, slick darkness falling around him like a wreath.

The tension broke. Someone screamed. The guests scattered, terrified, to the corners of the church, away from this Thing they'd entrusted their safety to, that had turned out to be just like the Things outside, dangerous and strange. One of them tried to stop Rose, blinded by fear and confusion, from stumbling down to his side.

She put one hand on his shoulder and shook it gently - no response - then reached for his hand, sought out a pulse. It was faintly echoed, like she'd always expected, but thready and terribly weak. Skin was hot, almost human-normal, which was positively burning up for him. Someone stepped up beside her, dropped the TARDIS key into her nerveless and shaking hand. She turned it over in her fingers a few times. It was cold.

"That's it," she mumbled through her tears, looking up to see her father looking down at her, standing beside her and the Doctor's still form, unflinching. "Nothing left we can do, yeah? It's over."

"No. It's not."

Her father was clever, it was where Rose got it from, in the end. He'd worked it all out. She argued and shouted and bargained with fate and finally just handed him the vase, the horrible tacky vase, and Peter Tyler walked out of the door and into forever.

She held his hand, and let go, and walked away, as she should have the first time. She wasn't used to having to let go, and she held onto the Doctor's hand all the more tightly to make up for it, as they made for the TARDIS. He looked normal now - pale, eyes pinched with exhaustion, and his jacket was torn up the back and yes, rather bloody, but the strangeness had passed and he was her Doctor again, her gangly Northern fellow with the haunted blue eyes.

But that wasn't enough, not for Rose. Grief alone craves understanding, needs to be made whole. She waited until they were inside with the doors closed and then asked tentatively, the question clear in her voice for all that it was warring with the impulse to just go off and cry. "Doctor...?"

"D'you mind if I get changed first?" he snapped over his shoulder, grinning faintly and there was both annoyance and humor in his tone. Normality, or an attempt at it. "Before you bring in the Inquisition? Just survived the end of the world and all, think I've earned myself the right to a clean jumper." For all the mock-indignation, he was speaking more softly than usual, and he was actually waiting on her answer - she nodded, and he disappeared into the corridors. Reappeared a few minutes later, bloodied green jumper changed out for blue, a dull black blazer doing duty work in place of his treasured jacket - he'd work on mending it later. Things could be mended, after all.

And it was that day again, so long ago, because suddenly there was something between them far more alien than the fact that the ship was bigger on the inside. The question echoed: "Where do you wanna start?"

"Th-the wings," she stuttered, fingers gripping the guardrail, white-knuckled.

"Yeah?" he said mildly, indulgence where there'd normally be irritation at her lack of specifics. She'd had a long and hard day. They both had. He crossed his arms and leaned against the opposite guardrail.

"What are they?"

"Wings," he snarked lightly, and woggled his eyebrows.

Rose sighed in frustration, looked off at some indiscriminate spot on the wall, over there. Third roundel from the right. She looked back up, nerves clearly shot, and she was being stupid, asking stupid questions. Time to fix that. "Right. Where are they now?"

He grinned, genuine warmth. "Astute one, that is. Tucked into a folded dimension. More of 'em than you lot realize, you know. Those creatures exist outside of time and space, it's an easy trick to just fold that little bit of 'em away."

She took a breath and bit her lip and looked at him expectantly, waiting for the rest of the explanation, the 'why' that all of her whats and hows were dancing around; he just looked right back, gaze even. "Alright, look," she finally said, exasperated, raw from grief, patience pushed to its limit. "Is there somefin' obvious I'm missing here, where I'm supposed to already know why you've got... stupid bloody Reaper wings in yer back pocket?"

He looked down then, suddenly unwilling to look at Rose directly, eyes clouding with some dark flicker of memory. Third roundel from the right. A measured silence, then... "I was travelling, with this friend. Little planet on the edge of nowhere. She made a mistake like you did today. Not for the same reasons, but for the same feelings. You're right there, and a bad thing's about to happen, easy enough to just reach out and stop it happening, yeah?"

"Yeah," Rose muttered quietly, understanding and afraid and sinking.

"You want the story?"

She nodded.

"You sure? It can wait if you want..."

"No," she said, clearing the last of the tears from her voice. "Tell me."