A/N: Sooooooo much love to beverlymaldoran and GrumpyJenn! (For full, extended thank-yous, view this story on AO3.)

Note: This story should probably be considered slightly AU as it heavily implies that the Doctor and River actually are living their timelines almost entirely front-to-back.

Enjoy!

They fell, laughing, into the TARDIS, barring the door behind them and sending her shooting into the vortex before collapsing in giggles against the console, leaning against one another for support. As their laughter slowly faded and their breathing calmed, River gradually became aware of skin against skin.

The Doctor had shown up looking a bit rumpled—shirt untucked, bowtie crooked, and tweed nowhere in sight—and River had smirked but said nothing. It was endearing and a bit ridiculous, of course, but she really couldn't have cared less how dishevelled he was when he came to her, as long as he was there.

But suddenly, she did care, because it was the smooth warmth of his bare forearm, protruding from his single pushed up sleeve, which now pressed against her own, drawing her undivided attention. Her skin tingled almost imperceptibly at the contact, and she jumped slightly. She nearly jerked entirely away out of reflex, but then she stilled herself as she realized that he seemed entirely unfazed by the press of their skin (a chaste yet shockingly intimate form of contact, which he too had yet to break).

She paused, contemplating him from the corner of her eye, wondering at her own sudden nerves. (He was only a man, after all. Although... she was only just getting to be familiar with this particular man. And, of course, they had never really been quite this close, for quite this long.)

She sincerely hoped he hadn't noticed her tense.

/ / /

The Doctor could hear—no, he could feel her heart rate increasing, ever so slightly; could feel her battling emotions and impulses radiating off her skin like heat from smouldering lava. He could almost feel the twist in her gut as she processed their closeness, and then the additional pang of confusion at her own unexpected reaction to it, and it made him feel so incredibly old.

He, too, had felt this once—what she felt now—and someday, a long time in her future (and his past), he would again, perhaps even as she felt what he was feeling now. Just thinking about it all made even his Time Lord head spin a bit, and he mentally shook himself to refocus his thoughts.

What exactly was he feeling now, though? It was hard to pinpoint, exactly. He supposed that, if someone were to paint it, it would be something of a caricature of what she was feeling now, beside him—a fact no doubt contributing to the ease of his empathy and the head-spinning sense of déjà vu—except it would be sadder. No. Not a caricature—a reflection. The same, but opposite. Sadness in place of joy. Knowledge instead of curiosity. Winding down, rather than up; darkness, instead of light.

But it was not all sad. It was bittersweet—it was all just beginning for her, and he could find it nowhere within himself to resent that, not even a bit. After all, he'd had his go. "You watch us run," she'd promised him—would promise him—and he had. And it was brilliant. His time was nearly through, and it was the best that he could have possibly asked for. Better, really, if he was honest with himself. And besides, she was there—she was with him, beside him, even if she didn't truly appreciate the significance of that fact, not anymore—No. Not yet.

So it was a darker sort of twist and pang that he felt in his gut, but it was tinged with light, just as the lighter one that she was simultaneously experiencing was tainted—almost imperceptibly—with the darkness of fear and uncertainty. Of... vulnerability.

"...Doctor?" she asked uncertainly, her breath a sweet breeze on his cheek. She had finally gathered her thoughts, only to find him deep in meditation of his own. "Are you... are you alright?"

He looked up at her quickly. He hadn't meant to drift off in thought like that—distracted by his own brain, as usual. He must have been silent for awhile, because there was mild concern touching her eyes, in front of the reckless excitement dancing with curiosity and confusion and fear and hope, all of which he had been contemplating only a moment before, and he cursed himself (not for the first time) for his own selfishness. Here she was, just beginning to discover the future of what they could be to each other, just feeling that first tingle of realization and possibility, and she had stopped, because of him. She was sacrificing that moment—a once-in-a-lifetime moment—to save him from himself. She was always doing that, sacrificing herself for him. Or, rather, he was always making her. (Or letting her, really. He should know better. Should have known better.) And she would go on doing it, he realized, right up until the end of them—right up until it was the end of her. Was this the beginning of that pattern? Was this when she learned to do it?

He shuddered at this, and snapped out of his morbid line of thought. He may have been approaching his own end - or at least the end of them - but she was not. She was just beginning, just finally beginning to understand, and she deserved to be happy. Yes, he thought. This glorious, glorious woman before him was brave and strong and magnificent, and she had ahead of her a lifetime of pain and hardship (and another lifetime of it behind her, even), and damn it all if he couldn't give her as many carefree and innocent days as he possibly could before she had to take the weight of the world—of all the worlds—on her shoulders, yet again, for his sake.

So he garnered his strength and smiled as if her question was silly, and if just a hint of his sadness still shone through, he could hardly be blamed; and anyway, the woman before him did not yet know him well enough to tell. "Of course I'm alright, dear. I'm always alright." He winked cheerily.

Later she would understand that this really meant "No, I'm not alright. I will never be alright when it comes to you." But for today, she just looked relieved - though slightly disbelieving at the 'always' bit - and rather amused at his cheekiness.

This would be a fantastic trip, he thought. Because it had to be. Taking a deep breath, he grinned his widest grin and scrambled to his feet, offering her his hand to help her up. "Well, I suppose we should be off then!" he declared with gusto. "You will not believe the trip I have planned for you this time!"

Leaning against the safety rails, she watched him fly around the console, limbs a blur as he moved through the familiar routine, and she pretended to sulk. "When do I get to choose where we go?"

He pulled the final lever with a flourish and whirled around to face her. He sidled over, contemplating her, a hint of humour in his eyes. "Maybe," he told her slyly, his smirk teasing but his gaze burning straight through her, "when you're older."