Clara was trying very hard to believe that the tiny wrinkle beside her eye was just her imagination. It was definitely the result of paranoia. It was her vanity making her nervous. Acting like such a silly girl. Right, of course. She leaned in closer to the mirror, pulled at the corner of her eye, smiled bitterly, relaxed. No, it was definitely the beginning of a wrinkle.

"Oh come on, Clara, you're turning twenty-five, not fifty-two," she sighed out loud, stepping back and smoothing her dress out, convincing herself to forget the wrinkle for now. It was her birthday, and she sure as hell wasn't going to spend it moping. Not when the Doctor was waiting outside to take her anywhere she asked.

Keeping track of time was ironically difficult when one spends time with the Doctor. It had something to do with the fact that today was her birthday, but she could have visited today a week ago, or she could go and visit her fifth birthday, except that would cause quite a paradox so the Doctor forbid such things. To keep some semblance of sense to her life, Clara had been keeping track of her days in a journal, and checking with the kids every time she got home to make sure she had only been gone the appropriate amount of time.

A quarter of a century old. One fourth of a lifetime behind her. Only three more of these to go. Her mind was still a jumble of a thousand lives lived and died, and now endings felt too raw—too familiar. Clara was feeling particularly morbid, but tried very hard to mask her thoughts behind a bright face, complete with a single, almost invisible wrinkle. She would be strong for her Doctor.

He was leaning against the doorframe of the TARDIS in the alley beside her house. He was checking the time nervously, ruffling a hand through his hair again and again like a schoolboy afraid of getting stood up. Since their return from Trenzalore, he had developed a sort of paranoia that at any given moment Clara would disappear from existence entirely and that would be it—the last time he'd meet his impossible girl. He had always felt protective of his friends, but never before had he known someone this long, or owed someone so much. And today, he had to put on a brave face and celebrate as she grew one year older—a reminder that even Clara would leave him behind someday. He would be strong for his Clara.

When she swung out the front door, she flashed him a smile that was maybe a bit too wide, and he returned the same.

"Well you look lovely! Something special about today, then?" he joked. She nudged against him playfully as she walked past into the TARDIS. She swallowed a few times, having to cast her eyes down and away from his hopeful smile, and suddenly felt as if she were holding back tears. She began fiddling with buttons she shouldn't be fiddling with to distract herself, scrolling through Gallifreyan messages on the screen that she couldn't read but stared at as if she intended to try.

The Doctor let his smile drop a bit. "Have you decided where you wanted to go?" He asked softly, breaking the silence at last.

As soon as the words left his lips, Clara spun to face him and blurted out, "Can you tell I'm getting wrinkles? I just want to know if it's in my head or if other people can actually, you know, properly see them, and I keep looking at it and imagining what I'll look like when my whole face is covered with them, and I think it really isn't fair that you're, what, forty times as old as I am but you have the face of a twelve year old and I just feel like I'm running out of time."

And then she spun back around so he wouldn't see the one tear that irritatingly dropped from her finely wrinkled eye.

The Doctor felt her words thud straight through his hearts as the realization hit that they were both feeling the same way about her birthday. "A thousand lifetimes aren't enough to contain Clara," he murmured, and let himself drape an arm around her shoulders. She immediately leaned her head against him, which made him a bit jumpy, but he held on anyway.

"Can we go somewhere loud?" she said at last, turning her round eyes up to meet his. He wrinkled his eyebrows together. "Somewhere loud?"

"Yeah. Somewhere with lots of people being happy and noisy and chaotic. Feeling alive, you know?"

He understood.

"I've just the place!" The Doctor shuffled away and began excitedly activating buttons and pulling levers and swishing through maps on the interface. "And to answer your question, I don't see a single wrinkle. And that's even with my special Time Lord eyes."

"That isn't a real thing."

"Is too!"

Clara chuckled despite herself. "What, like your twenty-six brains?"

"Twenty-seven," he corrected, pouting. Nothing got past this one. The TARDIS lurched into motion then and they clung to the railing as they hurtled through space.

"Okay, so, where and when?" Clara asked above the noise.

"Well it's still today. Figured we'd keep it Clara Day. But we're going to—ah, we're here already!" They lurched to a stop. The Doctor took Clara by the hand and pulled her excitedly out the doors and into a whirring mass of lights and music.

Clara's breath caught in her chest for a long moment as they spun about, taking in a three-sixty degree view. Above their heads, multicolored galaxies swirled and burst and seemed to rain down in sparkling shimmers, like fireworks. All around, alien tourists picnicked and shopped from vendor stalls and danced to strange music played on stranger instruments.

"It's an intergalactic collision storm. Basically a lightning storm between stars, instead of clouds. Very rare. But they last for millions of years, and this one is still going. It's sort of become a perpetual party to come to this stationary asteroid and watch," he was saying quickly, close to her ear because of the noise. As if to punctuate his words, a giant purple-red explosion hissed out in the sky above them, and below the crowed chorused a reverent "Ooo!"

"Happy birthday," he added, pressing a kiss to the top of her head. There was still sadness in it, but it was easier to get lost here. Their hands linked together automatically, and they exchanged a guarded look before Clara slipped into a shy smile. "Do Time Lords dance, then?"

The Doctor gulped and threw a wild look around himself, seeing that a large group of people were twirling about beside the odd, curling instruments. "Well, erm, technically—"

"Come on then, I'm not getting any younger," she dragged him into the crowd and they spent hours trying to lose the gravity of that statement amid mimicking the fluid movements of the others. There was no day or night here. There was no clock. There was no foreseeable end to the colorful dance in the sky. And so below, they danced on, timeless.

Finally Clara collapsed into his arms, laughing, cheeks red from exertion, both of them clapping for the band that played tirelessly on into the next song. The Doctor had been distracted, watching the way her skirt twirled out like a blooming flower when she spun, and the way her hair flipped energetically over her shoulders when she'd turn to look at him. In her breathless smile, he first noticed the crease beside her eye, and suddenly felt horribly small and useless to her. She had broken herself apart for him, lived over and over again through his life, and he could show her a dance beneath an intergalactic collision storm, but he could not keep her forever. The dance would end, and he was suddenly certain that he was incapable of facing another ending. Not with her. He felt too much emotion threatening to betray him, so he broke away and half ran back to the TARDIS.

She burst through the door after him, to find him rubbing a hand anxiously through his hair. He met her eyes then looked away again. "I'm…selfish," he answered her unvoiced question.

"So am I," she answered carefully. Stepping up closer to him, she wrapped a small hand around each of his suspenders, forcing him to look at her. "So what are we gonna do about it?"

Maybe it had been all the spinning and the colors and the explosions. Maybe the timeless stretch of noise and chaos had rattled something out of place in his mind that he otherwise would have kept tightly balanced and hidden away. Or maybe it was those warm brown eyes flickering expectantly between his and giving him the sensation of falling through space. But there was something he could do about it—he knew there was—he had just hoped he would never let himself believe in it. The Doctor opened his mouth, felt the words stick, swallowed, opened again…

"Doctor?" Clara let her hands drop down a bit, looking confused. She wasn't sure what she had been expecting, but it wasn't the look on his face right now.

He blinked, clenched his hands into nervous fists, stilled the beating of his heart. He knew, once he suggested it to her, once the words were spoken out loud, there would be no turning back. Then he jumped. Geronimo.

"We're going to get you more time."