Prompt: What If Rose never found the doctor at the end of series four, and itstead of River, Rose was the mysterious time traveler.

She has been jumping from universe to universe for so long, she is practically not human. Eleven doesn't like dealing with her, and there is this sort of pain and flirtation between the two of them.

He tells Amy and Rory that her name is "Bad Wolf".

"Erm. Doctor." Amy leaned forwards to whisper into her ear.

"Amy! Yes! What is it!" He whirled wildly.

"I think that woman—"

"Woman?"

"Rory and I noticed that woman is watching you."

The Doctor stopped so suddenly that Rory ran into him. "Where..." he said lowly, still.

"She's across the street," Rory said, rubbing his nose.

"Blonde?" The Doctor asked, tilting his head.

"Yeah. You know her?" Amy said.

"We need to go." He looked around quickly, darting down an alley.

"Doctor, I think I've seen her before!" Rory panted up next to him.

"Probably have!" the Doctor said distractedly, searching out the next path. It was only when they were safely behind the doors of the TARDIS that he stopped running.

"Okay. Okay, Doctor? That's not a natural reaction to a blonde," Amy accused, hard on the Doctor's heels. "What's going on. Explain."

"Yes. I second that thought. What the hell is going on?" Rory asked, coming up on the Doctor's other side.

Looking between the two, the Doctor's face flickered with emotion. He pushed his hair back on his head, staring into the console and then let out a yell and ducked from between the Ponds, running down the hallway.

"Woah. Touchy much?"

Rory nodded. "Um."

"Yup. Pretty much." Amy looked over at her husband, folding her arms. "We've got to find out who that woman is."

"Girlfriend?"

Amy rolled her eyes. "I don't think he's capable of having a girlfriend."

"That's unkind. I say wife."

"Wife? Rory! What did I just—"

"A wife is more likely to put up with stuff than a girlfriend."

"Ex-wife. Then."

They shared a glance and then shrugged, heading off to find the Doctor.

He didn't tell them. No matter how much they pestered, he always changed the subject and took them off on some wild chase on a new planet in a new world. Now that they were looking, however, Amy and Rory saw her everywhere. She was on the street corner on Darikus 5. She was on the rig with them when it was about to go down on Mallyn. She sat waiting for them when the exited the cafe on Ixckshyshus (Amy never could pronounce that one correctly). The Doctor kept this secret carefully guarded.

"Are you ever going to introduce me?" the woman said as she dropped into a chair next to the Doctor at the country club. Which made him shriek like a little girl and then rabbit up to his feet. The woman grabbed his wrist and yanked him back.

Amy and Rory jumped, Amy's eyes wide and Rory's mouth slack.

She smiled at them both, hand still firmly wrapped around the Doctor's wrist. She turned the expression up on the Doctor, eyes wide, her teeth pressing down on her bottom lip. "Well..."

The Doctor looked over at Amy and Rory, flickers of emotions running through his eyes as his lips remained pinched. "Amy. Rory. This is Bad Wolf."

"Bad—what kind of name is that?" Amy blurted.

Bad Wolf laughed, startling them both with the flash of gold from her eyes.

"Rory," Amy bit out of the side of her mouth, gripping the arms of the chair tightly.

"I saw it," he returned, leg jiggling.

"Oh come on! I'm not going to hurt you. If you didn't take all of your cues from this one, you'd take a look at me and see I don't mean any of you harm," the blonde laughed.

"Then why've you got his wrist in a death grip?"

She sighed and loosened her fingers on the Doctor's wrist. "I just don't want him running off is all. He's extremely hard to get pinned down." The smile suddenly seemed very dangerous. "Besides. He's just mad."

"I'm not mad!" He snapped, studiously staring down at the pavement, eyes wide.

"Doctor..." Bad Wolf whined, leaning against him. He stiffened visibly. She sighed and then sat, shifting her hand so her fingers were laced with his. "Fine. Be like that. You've been running so far, so fast, all to avoid me."

The Doctor said nothing.

"I'm not... Oh for the love of... Excuse me, Ponds. I'm going to borrow him for a minute." She stood and dragged the Doctor up with her. Heading off around the corner, the Doctor held his arm ramrod straight, bent away from her.

"We—"

"Are so following," Amy interrupted, dragging her husband after them, the two of them crouching down, stretching their heads out as if that would make them hear better.

"Come on. You couldn't just sit and talk to me for a spell?"

"Rose, you can't be here!"

"How do I look? Do I look like me today? Some days I don't, you know. I miss you."

"You have to go. I don't want you talking to Amy and Rory."

"Why? Newest flavour of the day can't meet the old favourite?"

Silence stretched and when Amy risked peering around the corner, the Doctor was staring away from the blonde woman, shoulders tight and neck bowed.

"Please go. I can't... I can't anymore."

Bad Wolf's brows drew in, more gold flashing through her eyes. "I miss you, you know."

"Oh Rose... I..."

"Yeah. Never could get the words out, could you."

"Stop it," he threatened lowly.

"Or what. You can't do anything. I'm Bad Wolf. I create myself! And look what I've created!" Her voice edged upwards, turning shrill. "Here I am, popping through universes! I've been as many places as you have now, Doctor! The least you could do is show me the decency of stopping and giving me the time of bloody day! After all, that's you—last Time Lord, and you've got all the bleeding time in the world, haven't you!" She dropped her arms ending in fists and sighed, so weary. "But you haven't got the time for me..."

The Doctor took a step forward, arms reaching out before he stiffened and pulled them back. "Rose, you've got to go. This..." He waved his hands at her. "This was never supposed to happen. It shouldn't have been able to happen."

"But I'm Rose Tyler," she said quietly. "Defender of the Earth. Stuff of Legends. But I'm only a half now, Doctor. I'm only half without you."

"Enough. I'm going. I have to go. I have to..." He looked around, still a bit dazed. "Come along, Ponds!"

Amy and Rory scrambled up from their hiding spot and trotted after the Doctor. "Stay away from him," Amy growled as they passed.

The blonde only smiled, so sadly that it took Amy's breath away and shook her head. "Take care, little waters. You too will dry."

Amy woke with a gasp that night, Rory tucked under her chin, arms wound around her tightly. He squirmed as she shifted, but relaxed away as she murmured, "Need to pee." She by-passed the loo and slipped out of their room, pulling one of Rory's over-sized shirts on before she left. Padding down the hall, Amy drew back into the shadows when a glimmer of light approached. She swallowed her gasp as the apparition passed her, a familiar blonde woman in glowing white. Amy crept after her.

Her first stop was a room in the TARDIS Amy had never seen before. After the ghostly figure left, Amy poked her head in, seeing it littered with things. It was all normal things any girl would own. A hair dryer. Big pink fluffy duvet. Slippers. A robe. Hairbrush. Shirts. Jumpers. Shoes. Dresses. It was a whole life packed into a room. She hurried down the hall after the fading light until it disappeared into a second room.

"Doctor..." The echoing voice said softly.

Through a crack in the door, Amy saw him look up, at her. Like he hadn't when they'd been at the country club. His eyes were deep and sad, full of memories. He wasn't surprised. The woman bent forward, kissing him lightly on the forehead.

"Do you think of me?"

"I can't stop," he murmured.

"Don't look so sad. It's not your fault. Always with the guilt. I know you changed. To throw me off. You can't let me go though."

"You can't let me go," he countered fiercely.

She smiled softly, kneeling in front of him where he sat on his bed. "I still love you. I haven't changed that much."

He closed his eyes, brow furrowed. "Go, Rose."

"Don't you need me?" She sing-songed, caressing his cheek.

Amy didn't miss the part where his head leaned into it while his body leaned away. And how Bad Wolf rose up to kiss his lips. And how his arms were suddenly crushing the woman to his chest. Amy jerked back. Pulling herself to her feet, she quickly ran back to the room she shared with Rory, easing into his arms even as her heart pounded wildly. It was a while before she fell asleep.