A/N: I'm so enamored with the dynamic between Twelve and Clara that I had to write this. Should be two or three more chapters coming. I was going to publish in one fell swoop but decided a few chapters might be a more palatable format.
I may have taken some liberties with the canon in this fic. I'm operating under the assumptions that a) it takes Clara longer to warm up to Twelve than we see on screen, and b) she remembers a bit more about jumping into the Doctor's timeline than she seems to. Hope you enjoy it nonetheless!
The way he piloted the TARDIS now – with reverence and deliberation, necessitating every spun cog and pulled lever and pressed button – was, in a word, off. It might have upset her. It might have fascinated her. Mostly, she was adjusting to how maddeningly new everything was and simply couldn't settle for a single word to describe how much their relationship had shifted.
Her Doctor had once been all arms and legs and whimsy, with a devil-may-care attitude toward piloting the time ship to places they hadn't intended to visit. This one . . . well, he remained a tall drink of water like his predecessor, to be sure. Clara had moved past the grey hair (it made him look more dignified, more scholarly), the crevices in his face (a touch too close to his Trenzalore days), and the punky waistcoat and Doc Martens (no one needed a reminder of the 80s but the ensemble did suit him) and was now scrutinizing his much-changed personality. He was harder to read, harder to corral, harder to like, honestly, and that presented her with a rather savory challenge.
She opted, however, to not let the Doctor know that while she acknowledged the shallowness of sizing him up, she also reveled in it. It was the last human pitfall she needed to traverse before fully accepting this new man.
At times, Clara was so dead-set on coaxing the remnants of her floppy-haired Doctor to the surface that she would interrogate him, often inartfully, concealing her true intentions by posing innocent questions. What was his favorite Earth city? His favorite school subject? And what was he prone to doing while she was away from the TARDIS? (Ancient Rome, Arcturian Light Mathematics, and waiting for her to come back, respectively.) The exchanges felt like awkward first dates, but she'd persisted. The question of his favorite food occurred to her once, while skimming the shelves on the upper floor of the console room. So she asked him what his favorite food was.
It took several seconds before his response came, and it was already tinged with annoyance. "Come again?"
She clutched a thin, honey-colored textbook to her chest and leaned over the railing. "Oh, you know. You probably like something eccentric that would make Gordon Ramsay hurl a saucepan at your head, yeah?"
"Like fish fingers and custard, I assume?" the Doctor said, not looking up from his calculations. "Terrible combination. Fishy and artificially sweet? Whoever thought the food version of Signora Calvierri was a brilliant idea?"
"You did, once upon a time." She smiled in jest, trying to keep the tone light.
"Different man, different stomach."
"What about, erm, Jelly Babies?"
He scoffed. "Decent enough until the second chew and the little gummy pieces get stuck in your teeth. These teeth aren't equipped for that kind of labor; I think I've got metal fillings now."
"Bananas, then? Or apples? Didn't you once wear a stick of celery on your coat?"
No answer.
"And for some reason, the one with the trainers hated pears." She carefully returned the book to its home on the shelf. "Maybe you're a veg person now? Or maybe the bigger question is what you don't like. You know where we should go? The Restaurant at the End of the Universe. Does that actually exist, or was it just Douglas Adams talking big?"
"It exists, and Douglas was a friend. Clara –"
"Then let's just go and have a nice –"
"Clara."
The Doctor's voice was loud, firm, and alarmingly close. He'd migrated noiselessly to a spot directly below her on the landing, hands resting in his pockets, fixing her with an expression that made her feel as if, despite her being on the second floor, he was towering over her.
"Okay," Clara breathed, "you've got to teach me how to do that."
"I think we both know exactly what you're doing," he said slowly.
Heat rose to Clara's cheeks. "I . . . wasn't trying to . . ."
A wan laugh escaped him. "Ah, see, that's the wonderful part about humanity: you all wear emotion like a second skin. However hard you may try to cover it, it remains on display for all to see. Desire, fear, jealously, anger – and in your case, longing."
"Longing?!" The scandalized tone had worked on his younger face; why not try it on this one? "What exactly do I long for?"
"The past," he said matter-of-factly. "Shame. I thought you were different than the rest."
Her heart lurched painfully. She descended the stairs until she was level with him. "We had this discussion."
"I know," he replied. The curt smile slipped. "So why are you still looking at me like I'm a stranger to you?"
"I—" Clara began, but the Doctor barreled right over her contrived apology.
"You've seen all my past lives. All the times I died to get to where I am. All the sacrifices I had to make. Of all the people I've brought abroad the TARDIS, I expected you to be the least affected by my regeneration."
Clara certainly hadn't intended to make him cross, but he was playing the part of the reprimanding headmaster and she was having none of it. Snippets of her charged conversation with Vastra rushed back to her, but she couldn't articulate now what she'd said then. She simply wanted a barb to throw at him, something that would hurt, and it tumbled from her lips before she could stop it.
"I'd just hoped it wouldn't happen in front of me!"
If her words stung, he showed no immediate sign.
"They don't teach people this in school! How to – to look at someone knowing they're the same person while simultaneously being so utterly, thoroughly different! I'm sorry, Doctor, I really, truly am — " he'd strode a few feet away from her, his own frustration clearly showing – "but I can't just flip a switch and make things the way they were between us!"
The Doctor swung around to face her, the tension between them now palpable. "'Sorry' is not a balm one uses to patch up a petty truth. I trusted you, Clara Oswald. Are you going back on that trust?"
Never mind the fact that she was unfairly attributing this temper to his newfound Scottishness; questioning her loyalty to him was not something she'd expected. Very quietly, she said, "If I didn't know better, I'd say you take my opinion to heart."
"You're right," he replied, sweeping past her, up the stairs, and out of the control room in a blur of black and red and silver. "You don't know better."
The moment he'd gone, a thunderbolt hit Clara: they'd just had a domestic, or as near to one as was possible for the Doctor. All the fight left her, replaced by a curious numb feeling she couldn't put her finger on. Unable to move, Clara sat down on the step and pondered the immediate future. Would he go be wrong in his wrongness and offer an apology later? Or would she be forced to seek him out and admit she was being a self-righteous prat?
In front of her, the TARDIS's center console whirred and chunked. Clara lifted her head at the reassuring sound, privy to the argument's silent witness.
"Do you ever get used it?" she said to what she hoped wasn't thin air. "Him changing, I mean. He is the Doctor, and he's proven that to me. But . . . he shouldn't have needed to prove it in the first place."
How silly, Clara thought, trying to communicate with an ageless living spaceship running on the infinite energies of the time vortex. She took in the blinking buttons and twisting circuitry, willing to interpret anything as a response.
"I don't expect you to say anything." She chuckled. "Even if you do, I suppose I'm too, ah, pudding-brained to know what you're trying to say. For all I know, you're probably angry with me, too, for not accepting him from the start. Just – if you have it in your power, I . . . I need help. Please. Help me understand him."
The TARDIS made a sound like a great beast exhaling, something it did when settling into autopilot, and Clara sensed the "conversation" was at an end.
After several minutes of staring into space, Clara collected herself and resumed perusing the bookshelves. But the chill the Doctor had left in his wake made her wish for sunnier days.