Disclaimer: I do not own Doctor Who. I'd have considerably less student loans if I did.

Rose Tyler does not scare easily. She has seen many things in her relatively short life - aliens, daleks, cybermen, alternate universes – things that would and should terrify ordinary people. But not her. She supposed that's why she had assimilated so quickly to Torchwood when she'd first arrived in this world. Nothing they threw at her could shake her. Nothing at all.

This is why she was so completely and absolutely crippled by the unfamiliar sensation of fear when she realized she'd lost the Doctor. Not lost him personally, like losing a child in the market, but lost him in the sense that he's disappeared and she has no idea where he is.

Her mind scrambled to make sense of the situation. She'd left him alone, here, in her flat while she ran out to her mother's, having left some things behind during their stay at the Tyler mansion earlier in the week. They'd only just returned, having spent their first few days in this world at her parents'. Her mother had been eager to keep her close and Rose hadn't had the strength to protest. The mansion had been a place of refuge while the two of them acclimated to everything that had taken place. Neither Rose nor the Doctor had imagined that they would have ended up back in the alternate world again, let alone together.

It had made perfect sense to leave him home. When she'd mentioned going to her mum's, he hadn't wanted to accompany her, claiming that he wasn't all that up to seeing her family again, and after spending so much time with them recently, she'd completely understood. With a kiss on his cheek and a smile, she'd vowed not to be gone too long. He'd told her not to worry and to take her time, and as she left he had settled on her sofa with a novel.

It had all been very domestic, she realized now, easy and effortless and she'd barely noticed.

Rose honestly hadn't meant to be more than an hour – it was, after all, the first time she'd left him on his own for more than a few minutes – but once she'd arrived, her mum had roped her into staying for tea. That, of course, had turned into a discourse about how she was doing and how the Doctor was doing and how they were doing… or not doing, as she'd informed her mother with a glare. And then there was Tony who wanted her attention and her father coming home from work and all of a sudden she looked at the clock and realized she'd been gone for nearly three hours.

She'd driven home as quickly as possible, feeling awful that she'd completely lost track of time and knowing that he was probably driving himself mad with boredom. It wasn't that she didn't trust him by himself, but that other than that novel and the telly (which he really didn't care all that much for anyway), she didn't have much in her flat to occupy him. And a bored Time Lord was something she did not want to come home to. She could scarcely imagine what he'd get up to all on his own – tinkering with her appliances or alphabetizing her sparse DVD collection.

But she'd never stopped to think that he might be gone when she returned.

She had entered quietly, half-expecting him to be napping, as he'd been wont to do since they returned – something about an overwhelming desire his new human body had for sleep, he said. When she hadn't discovered him sprawled out on the sofa, she'd gone to check the guest room. Not finding him there, she'd checked her room (just in case), then the bathroom, then the kitchen. Not finding him in any of those places, she'd called out for him, only to be answered by silence.

This is how she found herself standing in the living room, deafened by the silence, ignoring the hot flash of panic running through her.

Stay calm. Don't lose your head. Everything will be fine, she reminded herself. He can take care of himself. He's still the Doctor, after all. And how far could he have gotten, really?

…Depends on how far he wanted to go.

But if he wanted to leave, he could have done so long before now.

…But was he waiting for the perfect moment?

No, that's not like him.

…But it is like him.

Taking a deep breath, she double-checked the kitchen, looking for a note, a clue, something that would tell her where he was. No notes. Not on the dining room table either. Or the bathroom mirror. Or her dresser. Or his dresser.

In his room once more, she noted that most of his belongings were still there. She breathed a little easier. If he meant to leave for good, he would have taken his things… wouldn't he? She assumed so, but at that very moment, she didn't know. She just didn't know.

For the first time, she realized that she didn't really know what this man, this version Doctor was capable of. Of course she knew what he was like – she had spent years traveling with him and that relationship hadn't just disappeared – but the man with whom she now shared her flat was not exactly the same man. He looked, talked, walked, sounded like the man she loved, the man she'd fought so hard to get back to, but there was something… different about him. Good different, but new and a little bit strange all the same.

She just didn't know how much that difference mattered.

A fresh wave of worry washed over her and she sank down on his bed, laying her head on his pillow and breathing in the scent of him. She didn't know what to do. She had no way to find him. He didn't have a mobile yet – they had planned to go out and get him one tomorrow – and what good would it do for her to go running up and down the streets, shouting for him as if she were crazy? There was literally nothing she could do, nothing but wait for him to come back.

Just as she gave herself over to panic, there was the unmistakable sound of the lock being turned in her front door. Rose leapt up so fast she nearly tripped over her own feet. She reached the entryway just in time to see him step through the door, entering casually as if he had no idea of the alarm he had caused her. He probably didn't, but he would.

"Where the hell were you?" she shouted at him, surprised by her outburst of emotion. She hadn't meant to do that, hadn't meant to sound this clingy and demanding and possessive, but her fear and relief and tumultuous emotions were too much for her to handle right now.

He turned around slowly, his eyebrows raised. "What do you mean?"

"You disappeared!"

"I just needed some fresh air," he shrugged, gesturing to the door. "It was too quiet in here. I had to get out."

"So you just left?" she accused.

"You were at your mum's. I didn't think you would even know."

"Well, I do now. What happened?"

"I lost track of time. That happens to me now."

She registered the pain in his voice, but kept right on going. "You didn't leave a note!"

"I didn't expect to be gone that long," he repeated quietly.

"Don't do that to me again! Ever! Do you understand?"

He blinked at her, uncomprehendingly. "I can't leave the flat, then?"

"No… Don't be stupid. Just… don't disappear without telling me where you're going. Without telling anyone!" she huffed, her anger abating now that she's found him. The hot rush of emotion was slowly cooling in her veins, once more turning into the fear that she had felt so keenly just seconds before. She felt her hands trembling as she realized just how sharp and consuming the fear of losing him was – is.

"I'm not a child, Rose. I'm not a… pet that you need to take care of!" he rebutted, running his hand through his hair, clearly frustrated by her seemingly uncalled-for emotion.

"I know that, but you can't just go swanning off," she shouted back, hating the slight tremor in her voice.

"I didn't just 'go swanning off!' I stepped outside for some fresh air! Contrary to what you may have been told, I'm all right by myself. You don't have to watch me every moment. I can handle myself," he added.

"I know you can," she began, softer, brushing her hair back where it had fallen onto her face. "It's just… I didn't know where you were. I thought… I didn't know if…"

"If what? I'd gone and left you behind again?" he finished for her, still annoyed.

Rose didn't answer. She was frozen, struck dumb by his words. Yes. Yes, that was exactly it. Tears suddenly clouded her vision and when she looked up at him, she could see that he had realized just how his words had wounded her. His face softened and pain seeped into his eyes.

"Rose," he said softly, taking a few steps towards her. They'd become quite separated in their fight, in more ways than one, and he closed the distance between them effortlessly. She didn't flinch as he approached her, nor did she acknowledge his closeness.

"Rose," he repeated, bending his head to meet her gaze.

Just the sound of her name was enough to undo her, but she bit her lip, stubbornly refusing to look at him, focusing on the carpet, the wall over his shoulder, anywhere but his face.

"Did you think I had left? For good?"

She still couldn't look at him, couldn't let him see how weak she still is, that even after everything she still thinks that he could just up and leave her again without so much as a goodbye. But he did it once, more than once, and he might do it again. She can't face that. She just can't. And if she has to punish him with her silence now, then she will. She'll do anything to get the message across that she is serious and that being without him is something that she is not willing to do again. Not ever.

"Rose… you know I'm not going anywhere, right? You know I wouldn't just leave you."

She hesitated, and when she finally dragged her eyes to his, she saw in them that he had never stopped to think that she just might not know that.

"You know that I wouldn't just up and go," he continued, reaching for her hands. "I chose to stay here, with you. I don't want you to have a question in your mind about where I want to be. Because there's nowhere else I'd rather be. Honestly."

"I know," she whispered, stray tears falling down her cheeks despite her willing them to stop.

"But…?" the Doctor prompted.

"I just get so scared… What if something happens to you? I don't know what I'd do if…" her voice trailed off as her breath caught on a sob. "I can't lose you again," she whispered, brokenly.

The Doctor pulled her to him then, gently cradling her against his chest. She wrapped her arms around his thin middle and rested against his frame, steady and solid.

"I'm sorry," he whispered, his head bent, his lips brushing the hair at her temple. "I'm sorry. I'm so, so sorry. I never meant to worry you. If I had known…"

"I know, I know," she murmured. "I'm sorry I was angry."

"It's all right. I can understand…"

"Can you?" she asked, turning her tear-stained face to him again. "I've been left time and time again by you… him," she corrected. "You keep telling me that you're the same man, that you're everything that he is, and I want to believe you – I do believe you… but that also means that you might leave me again."

"I am the same man," he asserted, "but I have the opportunity to make different choices. Just because I made a mistake once doesn't mean I'm likely to do it again."

She heard the word mistake and immediately searched his eyes, seeing still the pain that she'd witnessed as he left her behind on a beach not once, but twice.

"I regret every day that I didn't fight harder for you, that I kept you trapped here these years. You… you never gave up hope. You found your way back to me. You commissioned that awful dimension cannon and threatened the whole of time and space for the love of me and… and I'm sorry to say that I didn't do the same."

"You burnt up a star to say goodbye," she tried.

He shook his head. "Not the same."

"But you weren't… you're not the same as you are now."

"I know," he said softly, looking down. His lips drew into a thin line and she could see the sorrow and embarrassment all over his face, the emotion sending a stab of pain deep into her chest. She knew how badly he wanted to be the man she'd crossed worlds for.

"I'm sorry. I…"

"No. No, you've nothing to be sorry for. There's really no way around talking about it. I'm not him."

Rose winced at the sound of her words turned back on her, but she had nothing to say in reply. She'd been dreading the moment – this moment – when she'd have to face them. She could never take them back, much as she wished she could, and she could never undo the pain she'd caused him when she'd said them. She opened her mouth to try to speak now, but he shook his head.

"Let me… Let me say this, Rose. I love you. He loved you. I love you. I'll not stop loving you. I'll not leave you. He made his choice to give you a chance to be happy, the kind of happy he could never give you, safeness and normalcy…"

"I don't give a shit about safe and normal!" Rose cried suddenly. "Did he think that's what I wanted?"

"What did you want?" he asked softly.

"I…I just…" she swallowed hard, thinking. "I wanted to be with him again. I wanted things to go back to how they were before."

"Things can never go back. Only forward. You know that…" He sighed deeply and met her eyes once more. "At the risk of being wrong and possibly doing more damage than I've already done, can I say something?"

Rose gave a half-hearted shrug. "Sure…"

"You say you don't know what you wanted, but I know you wanted to be with him. You wanted the adventure. You wanted the life you once had with him, the running and the adrenaline and the thrill of just being alive every moment of every day. Now, I can't promise that I can give you the same adventure he can, but I can give you a new one, one he cannot have, one he's not meant to have with you, but one that I think you want… somewhere deep down inside. I can give you my whole life, Rose Tyler. I can give you every moment – the big and the small – if you want. I can walk beside you from now until my final day. I can't promise you anything more than myself and the love that I have for you... and if that's not enough for you, please… please tell me now."

He grew quiet then and she saw his Adam's apple bob as he swallowed, carefully restrained tears making his eyes glassy. He was so open before her, laying everything on the line, waiting for her to pass judgment on him, to accept or reject him for all that he is and all that he is not. His unabashed vulnerability was new, and a bit frightening, but oh, so human.

"It's enough," she said, rushing into his arms, surprising him as she pressed herself against his body, her ear right up against his chest, listening to his heartbeat thud a steady, single rhythm. "I'm sorry I ever made you think that it wasn't. You've always been enough. Just you."

"And you're enough for me too," he kissed the top of her head and pulled back to look in her eyes, placing a hand to her face to cup her cheek. "You are. Please believe me when I say that you are."

She leaned into his touch, the warmth of his skin. "I know. You'll just have to prove it to me."

"If it takes a lifetime, I swear that I will."

"That's the answer I was looking for," she grinned and, on an impulse, rose up on her toes to press a kiss to his lips.

It wasn't like before, all passion and fire and urgency like when she'd kissed him on the beach in the wind and the cold with the shifting sand beneath her feet. But it was enough – sweet and honest and filled with promise for a life to come.

Rose sank back down and saw that he was grinning at her, that same madcap grin that crinkled his eyes and threatened to split his face in two. The smile that she risked life and limb and universes just to see one more time.

The Doctor reached down and grasped her hands in his, sliding their palms together and giving her fingers a gentle squeeze. She smiled back up at him, tongue tucked between her teeth, a giggle escaping her before she could stop it. The Doctor's eyes lit up at the sound of it and, as if needing to hear it again, he swooped her up, wrapping his arms around her in an embrace that stole her breath and left her feet dangling off the floor. Her arms about his neck, she clung to him, laughing and grinning into his shoulder.

He was here. He was here and he was real and he wasn't going anywhere. He was the Doctor and she was Rose Tyler. Just as it should be.

And she wasn't afraid anymore.