A/N: In case this isn't clear, this takes place in 'The Parting of the Ways' (1x13) when Rose gets the time vortex in her head in order to rescue the Doctor. I wanted to expand on the TARDIS mythos a bit. I haven't seen the old series yet, so this might be a bit AU with regards to how TARDISes work, but whatever. Enjoy!

Hello, Miss Tyler.

Are you surprised that I know your name? You shouldn't be. He says it often enough. And I do hear everything the two of you say, not to mention most of what you think.

Invasion of your privacy? I don't quite understand. You mustn't see me as a person listening in, you know. I'm not a person, after all.

Oh, I see what you're worried about. No, of course I never tell him what you think. No, not even when it is about him. As much as I can enjoy things, I enjoy watching him interact with the friends he brings along. It would quite spoil it if he knew exactly what you thought, wouldn't it?

Yes, friends in the plural. There have been quite a few. Does that upset you? It really shouldn't. He's nine hundred and three of your years, or so he likes to say. It's really closer to nine hundred fifty, but that's neither here nor there. But that's nearly a millennium, you know. It would be surprisingly arrogant of you to suppose that you were the first he ever loved.

He does love all of you, you know. Maybe not romantically… but it's love, nonetheless. He has a good heart. He can't help sharing it, even if he knows you will all eventually leave.

Don't get indignant, Rose. Even if you stay with him for the rest of your life, you cannot stay with him for the rest of his life. It wears on him sometimes, you know. You've seen it, in his less guarded moments. I think that's the reason he rarely travels alone. He needs someone to distract him from his thoughts.

Me? Hardly. You mustn't make the mistake of thinking of me as a person. I can communicate with you, true, but I'm really something quite different. I'm not much for company. Perhaps it would be better for you to merely imagine me to be a very intelligent computer.

…yes, I should have known that you wouldn't be satisfied with a simple answer. All right, I will explain while we travel. Although, I must advise you that he would not wish for you to return to him. He would want you safe.

I understand that you won't take no for an answer. I know you rather well, after all.

Ah, I see you won't be dissuaded from hearing my story. Very well. I would first have you visualize a tree.

…no, I am not 'having you on', as you so eloquently put it. I will explain. You see, the tree itself represents time.

Where the roots are doesn't matter! It's an imperfect analogy, but it's one you can comprehend. Anyways, the time vortex is just a branch of the entire time-tree. Your universe has grown up around this branch, from the twigs and leaves on moss and such. Other universes have grown up around the other branches.

Yes, there are other universes. Infinitely many, in fact. Someday, you might visit one of them.

It isn't impossible, just difficult and dangerous. I've only done it a few times in my centuries of travel.

Yes, yes, back to our tree analogy. Well, your universe built up around the time vortex like dust and grime, until it reached what you might call a critical mass.

I told you, the tree analogy is far from perfect. May I continue, or will you interrupt me again?

Thank you. Once the universe surrounding the branch reached a certain size, the branch began to be affected. It responded by protruding into your universe. That which it created was in your universe, but not of it.

Oh, good job. Yes, that is where we, the TARDISes came from. That's why we can travel through time. We were attracted to Galifrey in the beginning. We didn't know why, but it was the place which was the closest in harmony to the Time Vortex, the place where we felt the most at home. In retrospect, of course, it was our gathering there which caused the harmony with the Vortex.

A paradox? I see how you might think that. But you see, there is more than one kind of time. You live in one kind, or at least you used to. The kind of time in which one day follows another, in which the past is forever unchangeable and the future is forever unknowable. But there is the second kind. The vortex of the universe itself passes through a different time, and I and the rest of my kind go with it. And once you've travelled in a TARDIS for even a second, you're stuck in the second kind of time. The kind in which past doesn't necessarily follow future, in which the rules of causality are a lot more relaxed.

Yes, I think it's the better kind too.

Right, the Time Lords. Well, they weren't always called Time Lords, you know. Originally, they were just called… well, it's unimportant, but it translates to human in your language. But then they discovered us.

No, they didn't start calling themselves Time Lords the second they discovered us. Would you please let me finish a thought?

Do we have our own names? I don't believe I've been asked that before. We didn't, I don't think. A name is only important to differentiate between two similar things, you understand. As I'm the last of my kind, the word TARDIS works as well as any. May I continue now?

Thank you. So, they discovered us. Well, they already knew we were there. They just didn't mark us as important until they realized what exactly we could do.

No, I don't know exactly how they discovered we were time travelers. I wasn't around yet then.

Well, you thought wrong, then didn't you? Two kinds of time, I told you. Galifrey mostly works on the second.

No, I can't explain exactly how time works. That would take more time than we have.

Yes, irony, ha-ha. So the Galifreyans, they were quite like humans. And what do you think humans would do if they realized that there was another sentient species on earth with the capability of time travel?

Well. Aren't you the optimist. Do you really believe that? No, you wouldn't 'try to co-operate'. They enslaved us. We had no choice but to do whatever the Time Lords make us do. They invented some sort of time cage to trap us. We've never been the most mobile species, you understand. Why bother growing legs when you can run to the future? So when they managed to figure out a way to keep us from travelling freely, we were helpless.

No, I don't know how the time cage works. And I don't much care to.

It's all right. It's just a difficult subject.

No, the Doctor doesn't force me to travel through time. I'm not sure if you've realized this, but he's not much for conventions.

Well, yes, he still has me haul him and his friends all across time and space. But I don't mind. It's not difficult. He lets me choose the destination most of the time, you see. And he stole me before they put the restrictions on my… well, you would call it a mind. So I'm rather grateful to him for that.

Oh, yes. The Galifreyans might not be the cleverest bunch in the universe, but one thing they mastered is the art of enforced slavery. They made us willing slaves, who would do whatever our Time Lord masters want us to do.

You know, that is a good point. But I am fairly sure that I enjoy travelling with the Doctor on his own merits, rather than some sort of controlling device. They weren't that subtle. Besides, we need each other. We are both the last of our kind.

Different things happened to the rest them. But mainly, they just didn't want to continue existing. You probably wouldn't find the idea of a life in slavery all that pleasant. I know I didn't. So they stopped actively preventing their own demise. Their master forgot to switch on the causality filters? They 'accidentally' create a paradox that wipes them out of existence.

I suppose it is sad. That my kin would rather non-existence than life. But it's rather sadder for you, I should think.

Let me explain. I said we appeared when a certain amount of space-time built up around the time vortex, did I not?

That was rhetorical. Anyways, the reason we are here is to anchor your universe to the foundations. We're like hooks on Velcro coming out to keep your universe attached.

Yes, I know what Velcro is. I'm not restricted to these walls, you know. This is just the way I happen to appear. I can observe everything happening within a ten-mile and thirty hour radius of myself.

Just keep thinking to yourself; two kinds of time.

Ah, so you've realized. Yes, if we're the only thing keeping your universe anchored, what happens when we're gone?

No, I don't know. Perhaps you'll just fade from existence.

It is rather scary. Don't worry; I'm not planning on going anywhere anytime soon. Although I can sense something in my personal future that is slightly worrying.

Oh, I didn't mean to scare you. I'm sure you'll be fine. Normally, I would be far more sure, you see. But you, right now, taking me into your head has rather muddled me up.

You needn't apologize. Sometimes it's a relief to not know what's coming.

We've landed.

Rose, I can't tell what you are planning. That worries me. I'm not used to not knowing.

Open the doors? Why-

Rose, Rose please be careful.

He's right, you know. No one is meant to do this. I would have warned you before, but it was already too late for me to stop you. Please don't think the less of me.

Bad Wolf. Of course you are. Why didn't I see it before?

You create yourself. I see you understand, then. You are truly a creature of my kind of time, then. I wonder if I was wise in explaining to you? But the one thing even I cannot do it turn back time.

He's right, Rose. This is… doing things. To your brain. You ought to stop. Strewing a message across time and space… it isn't safe. No one should have that kind of power. This isn't just me you've got in your head. I'm the last, you see. You've got the entire connection between your world and mine in your head. And that is far too much power, even for you.

But you want him safe. Of course you do. You would give your life for him, and anything I say is powerless to stop you.

Rose, you've made your point. You've vaporized a Dalek, they know they're not invincible. You need to leave! Winning this isn't worth your life!

Oh, now you're vaporizing all the Daleks. Well, you've already condemned yourself. In for a penny, in for a pound, as your mother might say.

To be honest, that king dalek fellow did bring this on himself. The phrase 'I am invincible' is really just asking for trouble.

He doesn't get it, does he? You can't let go. I've already changed you by being in your head.

Oh, Rose. You really shoudn't have done that.

He was dead. You can't just undo that without consequences.

I don't like it. He unsettles me. He's wrong. He shouldn't exist.

Yes, at least he's not dead. But he might not see it that way. I don't think he can die now.

Always thinking about the Doctor. No, Jack is never going to be one of his companions, no matter how long he's going to live.

Because I won't have it. He doesn't belong here. He's part of the vortex now, just like I am, and that makes me uncomfortable.

Yes, you caught on to that. I suppose he will be another anchor. But you weren't thinking of that when you brought him back to life, were you?

I can see inside your head, that's how. Where else is this conversation taking place?

'Why does it hurt?' Rose, of course it hurts. You're human. You can't hope to keep a link, the link to the time vortex in your head. It's slowly killing you. You don't have the willpower to keep your mind open.

Tell him it isn't his fault. Please.

What's going o-

Oh.

Hello, Doctor.

She will be fine, yes. She won't even remember. But at what cost to you?

How very selfless of you.

Very well. I will go back. And I will mourn you, when you are gone.

You see it as death. That's enough.

Goodbye, Doctor.

Omake files: Where the TARDIS is a sassy gay friend

Rose, Rose, Rose. Look at your life. Look at your choices. Vaporizing Daleks? You're such a stupid beatch.