Inspired by a tumblr prompt and references events of In the Blood by Jenny T Colgan. It takes place after the story has ended. I do embellish it a little, but there are spoilers!

"I was actually awake when you did that thing"

Promise

Donna was not in the kitchen. Or the pool. She wasn't even in the library. Not the the Doctor expected her to be there. It never was her favorite spot in the TARDIS, even before The Library.

He frowned as his footsteps echoed through the corridors. She'd been quieter after returning from her friend's house and they'd decided to coast through the vortex for a few hours. Both needed some deep breaths before setting off to wherever else the ship would take them.

Pausing in front of her closed door, the Doctor's hand twitched, so tempted to knock on her door to see how she was doing. Her words echoed in his mind, things cried out in a alien-driven mania as she came so close to death.

Did she really believe those things?

His hand came closer, hovering next to the panel, but then he pulled back. How could he have started such a conversation, even if she wanted to have it? Donna and he didn't always have those deep heart to hearts conversations. He sighed, wishing, not for the first time, that maybe they could. It would be nice.

Backing up, he shuffled his feet as he walked along to the main room, his mind pulling at less active and more relaxing places to take his Earthgirl.

It was quite a shock then, even to the Doctor, to see Donna Noble quietly sitting on the jump seat.

"Oh!" he exclaimed, rocking on his feet.

She pulled her attention up toward him. "Hey," she said softly, but not sadly. She sounded more reflective.

"I thought you were in your room," he confessed.

She shrugged. "Felt like bein' out here."

He nodded and walked further inside, noticing what it was she was holding: the crab-like prongs of the Chameleon Arch. He must have left it lying around after…after he'd changed back. Seeing it made his insides tighten.

Donna twirled it around on her palm, thinking. After a long beat, she looked up at him. "What did you call this? Champion Arch?"

He shoved his hands in his pocket, still feeling twitchy. "Chameleon Arch."

She glanced down at it again. "And what's it do?" When he didn't answer right away with his normal science-filled technobabble, she looked up again. "It made you human?"

He nodded.

Her eyes widened. "All of you?" she asked, and he nearly chuckled at the image that must have been playing through her mind.

"Yes. Originally, I was only going to make my blood human," he explained and then frowned. "But I had to do the calculations in a rush and so I ended up making everything human after all. It wasn't the most comfortable of things and then - " He stopped short, his memory slamming into the horrible memory of Donna Noble, nearly at death's enraged door, charging at him. He took a deep breath. "Yeah, you've got some Doctor blood in you now."

She grimaced, and the tension somewhat broke. Yet she still looked like something was on her mind. Placing the chameleon arch on the console, she pushed herself to stand behind the chair. "Thanks," she said quietly and looked almost guilty. "You did that for me."

The Doctor walked closer, hating that self-loathing in her voice. "Of course I would," he said, his voice harsh with conviction.

She rolled her eyes. "Yeah, I know you'd do it for anyone…" she said and flicked one of the prongs of the arch with her fingers.

He leaned closer. She snapped away, but he didn't move. "You said you were going to be with me forever, Donna Noble. I'm going to do my darnedest to make sure you keep that promise," he said.

They remained still, and it made his hearts sink that he wasn't getting through to her.

"I could hear you, you know," she said softly. "At first."

He blinked.

"Well, I don't know if it was at first," she clarified. "But I could hear you. When you were human. Talking about me tripping or some nonsense about hot chocolate."

The Doctor gulped.

She pursed her lips. "I remember your hand, too," she said. "Your hand on my forehead."

The Doctor didn't think it was possible for time to stop inside a time machine.

Donna looked up. "I was awake for that, you know," she said, her voice thin, as if she dared not believe her own memory. "You said something else, too." She stared forward. "Something quieter…"

He half-dreaded she'd repeat it. The other half of him was desperate for her to say it.

But she sighed, sparing them both. "Thanks for always believing in me, Spaceman," she said instead and rolled her eyes. "I can't believe all that stuff I shouted."

He exhaled. "You really do believe all that?"

She frowned as she fought the glassiness forming in her eyes. "Sometimes I do, I guess."

His fingers twitched again, but he didn't dare touch her at that moment. Not with her memory resurfacing. "I meant it too, you know." She looked up at him, and he smiled. "You are the exact opposite of all that. To me. To the universe."

She smiled tightly. "Yeah," she spat out.

The Doctor smiled, feeling a sort of return to normal that was both comforting and oddly sad at the same time. He reached over and took the chameleon arch.

She frowned at it. "I hope you don't have to use that again," she said.

"Me too," he agreed and turned, finding solace in the silence.

"Don't worry, either."

Her voice was quiet, but it was more forceful than her mightiest shouts. The Doctor remained in his spot, not sure he could turn to face her.

He heard her rub her hands over her arms. "I won't leave you," she said.

The Doctor turned, relieved his hands were filled.

Donna smiled at him. A gentle, friendly smile that made the Doctor's hearts race.

"Don't you dare," he said, and grinned back. With a lightness returned to his soul, he practically skipped down the hall.