She knew she was doomed the moment she slipped.

Rose sprinted down the corridors, just managing to keep up with the Doctor's long-legged pace. Skidding around the corner at high speeds, she tried not to think of how close their scaly would-be captors were behind them. Honestly, all it took was one word in the wrong place and suddenly your being dragged away to a cell by aliens. Well, maybe it would have helped their case if they weren't looking to shut down said aliens' business. With a quick glance back, Rose determined that the oversized toads had lost them.

Well, she hoped.

"Just a bit more, Rose. Come on." the Doctor called encouragingly from in front of her.

Another turn and the corridor ended abruptly. Rose screeched to a halt to avoid running off the end of the floor. In front of the pair lay an impossibly vast room. Down on the floor about fifty metres below, giant vats of multi-coloured liquid sat bubbling and oozing and steaming. Some looked thick, others thin, and still others looked to have chucks of unknown solids floating around in the mixture. The walls of the room were sheer and dotted with openings from other corridors in the building. As Rose craned her neck upwards, she could see a network of criss-crossing grated bridges crossing the gap over the products.

They seemed to be at the bottom level, only a few metres from the tops of the open containers.

"Well that explains where they've been storing the product…" the Doctor muttered, gaping at the immense size of the operation.

The Doctor and Rose had arrived on the planet earlier in the week with no plans to infiltrate an underground bath product organisation. Even so, Rose was anything but surprised when they caught wind of the horrors that lay brewing behind closed doors in the city. Between Rose chatting up the locals and the Doctor breaking into the national police database, they'd learned of a secret group of the aliens mixing up some extra powerful, extra illicit soaps; apparently for some, the scrubbing powers that be just weren't cutting it under the scales and in-between the gills.

Neither she nor the Doctor had seen the problem at first. Digging deeper though, tales of shampoos gone bad and overly effective facial cleansers had the stuff of legend on the case. Either someone was tampering with the products, or they had an evil scheme on their hands. Yet again. Sometimes, Rose wondered if it would be nice to have a cut-and-dried vacation from saving the world, but deep down she knew it just wouldn't be the same without running for her life at least once.

Their first two days on-planet had been wasted in a fruitless effort to find anyone close to the organization willing to cooperate with them. Everyone was keeping silent, lest they be thrown back into a world of crusty, dried out scales. Or worse, find themselves the next owner of acidic shower gel. On the third day, however, Rose managed to find one youngster who'd lost his mom to the effects of a particularly fizzy bath bomb who was willing to help.

The boy's cousin worked in the underground factories. Before the day was out, the Doctor and Rose they managed to weasel their way into operations with a cover story; two travelers, bound for greater things, but in need of a little cash to give them a push. Not that far from the truth, Rose mused. Though their money problems only extended to the Doctor's very convenient lack of earth currency every time they visited the chippy.

Three days into their undercover ops, of course, they were found out.

And so the chase began.

The Doctor gripped Rose's hand tightly in his own and lead her onto the bridge. The bridge rattled with every footstep and creaked unsettlingly. Rose reached out for any kind of railing, but was disappointed to find nothing between her and a straight drop down to the factory floor below.

"So what's down there, d'ya think?" Rose asked, cringing at the smell wafting up from the vats below. "Evil shampoo? Villainous soap? Illegal bath bombs?"

The Doctor laughed. "Who knows? Nefarious shaving gel maybe! Unlawful bubble bath!" Before he could joke any further, a loud bang sounded behind them, and Rose could just faintly hear the sounds of footsteps. The Doctor took one look behind them to asses the situation, then turned back to Rose. "Time to go!"

Dropping Rose's hand, the Doctor searched his pocket. A few seconds of fumbling with his arm in his pocket up to his elbow and he let out a triumphant "Aha!" as he brandished the sonic in his hand. He flicked through the settings and sent a quick zap in the direction of their pursuers before running onto the bridge.

Rose ran to catch up, but didn't think to watch her feet until it was too late.

Her left shoe slipped first. She felt her weight shift drastically and brought her right foot forward by reflex. Her right shoe slipped on the same patch as the other and gravity pulled her further backwards. Her equilibrium lost, Rose tumbled backwards, her hands scrabbling to catch her weight, but met with nothing but air. A wave of panic rolled over her as it clicked in her brain that she was falling over the edge.

"Doctor!" she screamed.

The Doctor whipped around in an instant, but he was too far away.

"Rose!"

There was a moment that stretched out for an eternity as Rose fell. She was transported back to the time as a kid when she'd jumped off the high-dive at the pool. The wind and the weightlessness and the sheer terror as you realise you're past the point of no return. When you know you're going to hit the water whether you like it or not.

In true justice to her memories, Rose landed with a splash.

One moment she was surrounded by nothing but air and the next she was engulfed in yellowy-green muck. The impact was almost as bad as hitting solid ground. Rose met the surface with a smack, and every ounce of air in her lungs was pushed out in a single breath. Before she had any chance to recover, the viscous liquid yielded under her weight and swallowed her whole.

The gunk burrowed its way into her nose, eyes and ears. Helplessly, Rose waved her arms in a vain effort to swim, but her weight was pulling her towards the bottom of the vat faster than she could ever hope to push against it. Her lungs burned and her head was spinning. With her consciousness failing her, she made one last desperate attempt to escape, but it was no use. Her instincts taking over, her mouth opened of its own accord and she breathed in the thick liquid.

Spots danced on the backs of her eyelids and Rose felt lightheaded and dizzy. Just as she was about to lose consciousness, she felt something tightening around her wrist.

In a flash, the chord around her wrist tugged her upwards (or she hoped it was upwards) and to the surface of the vat. She heard herself break the surface of the liquid, but the thick covering of the goo kept her from sensing any real difference.

Coughing and sputtering, Rose spat out what she could of the thick liquid. Pain seized her oxygen-deprived lungs, but it was blissful compared with the suffocation of before. Another tug, and her body was lifted free of the vat. It was only a few seconds before her hand hit the grating of the bridge. She scrambled for a grip on the ledge and felt a hand firmly grip her slippery arm.

The Doctor hauled her back onto solid ground (or, well, as solid as she was going to get) and wiped the mess from her eyes with a clean bit of fabric. Rose managed to pry open her gluey eyelids and started up at the Doctor, who was wearing a triumphant grin and loosening a knot from her wrist. A knot connected to a very long, very colourful length of fabric…

"Haha! Always have a scarf on you, Rose Tyler! Never know when it may come in handy! Did I ever tell you that I was crowed lasso champion on Renus Prime? Can wrangle a cow at fifty paces! Of course, they weren't really cows, and it wasn't really a lasso, but the concept's still the same. I managed to pull one Rose Tyler from a large concentration of goo with only one scarf and some good aim!" He beamed like a child eager for a prize.

In any other circumstance, Rose would have hit his arm for taking so bloody long, but as it was she was far too concentrated on making sure she didn't slip again in her now slick trainers.

A loud crash had the Doctor looking worriedly behind her.

"Think you can make it back to the TARDIS?" He stuffed the scarf back into his pocket.

Rose spat one last bit of the muck out of her mouth and nodded. "I think I'll manage. If there's anything that can get me moving, it's the thought of a shower."

The Doctor grinned and grabbed her hand. "Allons-y!"

•••

It was a good fifteen minute run back to the TARDIS. Rose only slipped a total of three times, and to be fair, one of those times was because the Doctor slipped on one of her footprints first.

Entering the console room, the TARDIS gave a warm hum of greeting, but the pitch of her song soon rose to an annoyed whine when she became aware of her passenger's state. Rose rolled her eyes, reminded of the time the TARDIS had used the same tone with the Doctor when he came in with a melting ice cream cone.

"Sorry girl. I know you don't like me dripping through the grating, but I didn't really mean to be covered in this stuff in the first place."

Another hum, and Rose saw a towel materialise on the railing. The Doctor's face lit up.

Before Rose could reach it, he grabbed the towel for himself. "Aha! Just what I was looking for." He wiped off the goo that had rubbed off on him and held up his hands for Rose. "All clean now!"

Rose dripped, unamused.

The Doctor looked at her blankly. "What?"

Rose scowled.

"What?! You said you were going to have a shower!"

With that comment, Rose scraped a handful of the goop off her and placed it on his head.

"ROSE!" The Doctor squeaked in alarm. He tried to wriggle away, but Rose grabbed him by his shoulder and rubbed the mess into his hair and smeared it down his neck.

"Rose stop! Stop! Oh ew!"

Rose laughed. "You're such a baby, you know that? It's only fair that you're messy too." In lighting speed she leapt into a hug, the Doctor still trying to escape ineffectively.

"How is that fair?! Rose, let me go! You're getting it on my coat! I love this coat! Janice-"

Rose sighed and let her victim loose. "Yeah, I know. Janice Joplin gave you that coat."

Holding his hands away from his body in a comical fashion, the Doctor made a purely disgusted face as he surveyed the damage done to his person. A stray clump of goo slipped from his hair and plopped onto his nose and Rose had to giggle.

"It's not funny, Rose," he said, scraping it off gingerly with a finger. "Now I'm going to need a shower. I had plans, you know!"

Rose rolled her eyes. "Oh boo hoo. I'm going to go get this stuff off. I'll be in my room if you need me."

She sensed him starting to say something before he even opened his mouth. "And no, you're not borrowing my banana shampoo again. You used the whole bottle last time!"

•••

The shower was miserable.

Rose peeled off her clothes and immediately decided to toss them. No matter how much she loved these jeans, there was no hope of getting the yellowy gunk out.

Stepping into the shower, Rose blasted the hot water. To her dismay, the gelatinous goop refused to wash off. With a little scrubbing, it started to come off, but there was no hope of washing it off under the shower's spray alone.

Twenty minutes later, Rose felt confident that she'd finally rid her body of the worst of the mess. She looked at her destroyed loofa mournfully. This was the fourth one she'd been through in the past two months. She wondered if the Doctor had problems like this. Did he even have the same bath products? Maybe he had some alien scrubber that specialised in scraping off goo. He could have a whole bathroom full of futuristic products and she'd never even know!

Rose was instantly indignant.

The nightmare worsened when she got to her hair. She tried three shampoos and two combs, but the only way to get it out seemed to be to wipe it off, strand by stand.

By the time she was finished, Rose was tired, sore, and ready to flip into bed and no think about bath products for the next hundred years. Wrapping her body in one towel and her hair in another, she opened the ensure door and padded into her bedroom.

Where the Doctor was standing, dripping water on her carpet, looking concerned.

"Rose! The goo! I think it's-"

She never got to hear the end of his sentence. In one sudden moment, Rose felt all the blood drain from her head, and struggled to stay standing. She coughed into her hand and was shocked to see bright red liquid on her fingers. So maybe that's where the blood went… She couldn't dwell to much on the sight though, as saliva flooded her mouth. The Doctor's gaze shifted from concern to alarm, and Rose struggled to explain her predicament.

"Doctor, I don't feel very g-"

Unfortunately, her stomach chose that moment to clamp up in a most unpleasant way. And like that she was sick on the Doctor's newly cleaned feet.

As if the last of her energy went the way of her breakfast, Rose felt her knees buckle, and slumped over into the Doctor's arms, unconscious.

•••

"Rose. Time to wake up now, Rose. I know you humans like your REM, but I need to check a few things."

The first thing that hit her was the dry throat. Or, well, it was scratchy. And... Stringy. Like she had a really bad wet cough that decided to get stuck halfway up her throat and then got baked in sandy heat. Her tongue felt like a too-large lump of clay, sitting uncomfortably in her cotton-filled mouth. She cracked her eyes open and pain blossomed behind her eyelids. She shut them again quickly, but not fast enough to avoid the eruption of pain in her skull.

"Ooohhhheeugh," she moaned.

The Doctor's cheery tone was in stark contrast to her own mood. "Now that's the sound I like to hear. How you feeling? Sore throat? Sore head? Queasy stomach?"

At the sound of his words, Rose felt her stomach twist and contract.

"Not until you SAID something!" she snapped. Okay, talking? Bad idea. BAD idea. "Eugh… Doctor…"

She felt a bowl being placed on her lap and two hands gently lifting her into a sitting position. The hands then fluffed and repositioned the pillows behind her to support her back and neck. It was a wonderful gesture; one that she might have appreciated it a bit more if she wasn't so focused on keeping her digestion a one-way track.

A tickle rose in her throat and she coughed, trying to clear it. Not good.

Retching and coughing into the bowl, she found that her insides had nothing more to give than a bit of bile.

"Ughhhh," she groaned. "Why is it that my stomach insists on malfunctioning when there's nothing left?"

Even with her eyes closed, Rose could practically see the Doctor tilting his head in his usual pondering gesture. "Well, it's not malfunctioning per se… It's not the most finely tuned human reflex, I'll give you that, but it's got the right idea. Rid the system of the toxins. Out with the bad!"

Opening one of her hands with his own, the Doctor placed a small slip onto her palm.

"This ought to take care of the nausea. Just put it on your tongue and it'll dissolve."

Rose groaned again, this time with a little more annoyance. "Doctor, there is no way I'm going to be able to dissolve that thing. I have no spit." She stuck out her tongue to demonstrate.

"Right! Yes! Of course, sorry. Here, I've got just the thing."

He fumbled for something in his pocket and drew out a blue cloth, handing it to her.

"Suck on this."

Rose risked prying open one eye to give him a look.

The Doctor blushed and fumbled, shoving the cloth into Rose's free hand. "Oh just take it."

She took the cloth and cautiously placed it in her mouth. Immediately, Rose felt the cloth dampen and a cool sensation spread across her tongue and around her mouth, as if she'd been eating a mint. Eagerly, she sucked on the fabric, and a small bit of liquid trailed down her throat with the same soothing effect.

"See? Not so bad. I'm not sure you're going to be able to hold anything down right now, but the medicine slip should help with that for the time being."

Rose hummed gratefully. Her body felt sore and battered, and her head was still killing her, but it was a definite improvement from when she'd woken up. Now that she was feeling a bit better, though, she noticed the chill of the room and shivered.

The Doctor placed his hands on her goosebumpy arms. "Are you cold?"

Not waiting for and answer, he grabbed the covers and rather than pull them onto Rose, pulled them clean off.

Shocked, Rose let out an indignant "Oi!"

The Doctor didn't acknowledge her exclamation, but shifted from his position on the bed. Rose felt her cheeks flush as he crawled over her body, and managed to stifle a squeak when he placed himself beside her on the bed and snuggled into her side. He pulled the covers up over them both and leaned over to tuck the blanket in on both sides.

Seemingly satisfied with his work, he patted the top of the blanket and grinned. "There we are then! Snug as two bugs in a Trilixian rug! Did you know that the Trilixians use tree bark to make their rugs? Doesn't sound very comfy, I know, but it's surprisingly comfortable. Especially for wood lice. That's what we are, Rose! Snug as two wood lice in a Trilixian rug!"

Before Rose could ponder the relative snugness of alien rugs, the Doctor pulled her close to him and cloaked himself around her. She sighed contentedly and leaned back against his chest. Her head fit just perfectly under his head and in the crook of his neck. She let her muscles rest and listened to the comforting rhythm of his dual heartbeat. Snug as a bug indeed. She felt safe and relaxed and warm… Wait. She opened her eyes tilted her head to look up at the Doctor.

"Doctor?"

"Hmm?"

"You're warm."

"Why yes I am. Good observational skills. A plus."

Clown. "But you're usually a bit colder than me, yeah? I mean, I can not count the number of times I've been this close to melting on the pavement and you're standing there in four layers!"

The Doctor rolled his eyes dismissively. "Superior internal temperature regulation, Rose. You lot spend way too much energy sending heat to your extremities. And with only one heart to do it, too! Point is, when I need to I can send a little more blood where it's needed. Like my hands, for instance."

With most of her discomfort gone and the Doctor cocoon she found herself in, Rose was growing sleepy. "Don't think I'll be forget about this next time I fall in a snowbank, mister. You're going to be spending all your time keeping me comfy, now." She yawned.

The Doctor chuckled and placed a small kiss on the top of her head. "I can imagine worse jobs. Now you should rest. Best thing for sick humans. Sick Time Lords too, much as I loathe to admit it. Some tea couldn't hurt either. Tannins and free radicals, that's the key. I'll be sure to make you some when you're done your nap."

Rose let loose another yawn and her eyes drifted shut. The Doctor wiggled down until they were lying down rather than sitting.

There was silence for a few minutes. Just when Rose was on the edge of sleep, she felt his hand combing gently through her hair. His fingers just barely grazed her scalp, but it felt so nice that it almost lulled Rose into slumber, but his voice caught her attention.

"I'm so sorry Rose," he whispered. So, so quiet. She almost didn't hear it. Now that she had, though, she couldn't let it be. Whatever he was feeling guilty about, if she didn't say something now, chances were he'd hidden away in self-flagellation by morning.

"What are you sorry for, Doctor?"

Rose felt him startle, and his hand quickly flew away from her hair. He didn't answer her.

"Doctor. What is it? Why are you sorry?"

A few seconds of silence, and then he whispered, "I'm sorry I got you sick."

Rose pushed herself away from his to look him in the eye. His expression was wracked with guilt. His eyes seemed to beg her forgiveness, though why he thought he needed it was beyond her.

She didn't know what to do to reassure him, so she fell back on what they always did in dire circumstances. She gave him a hug.

"Doctor, it's not your fault," she said. She hugged him tightly as if she could squeeze the guilt away. "You saved me. I'd still be in that vat if it wasn't for you."

He scoffed in self-deprecation. "You wouldn't have been in the factory at all if it hadn't been for me. I took too long. You fell and I couldn't even move. It took me so long to think of how to save you. Far too long."

Rose felt his agitation grow. His hearts sped up and he wiggled restlessly in her embrace. Even so, he made no real move to escape her arms, so she continued to hold him.

"I wanted to jump after you, but even if I could have climbed out with you, we'd have been stuck down there. And I didn't know if you'd be able to grab the scarf, and I couldn't do anything but sit there and hope that you weren't…"

Rose let him go and sat up. She gave him a stern look and he shut his mouth with a click. She grabbed his face in her hands and tried to smooth out the harsh lines of worry on his forehead. "Doctor, stop. It's not your fault. And you got me out. You saved me."

He shook his head lightly. "No. It's my fault that you ingested that stuff, and it's certainly my fault that I didn't realise what it would do to you. If I had just taken a moment to think… If I hadn't been so… so stupid you wouldn't have been sick at all!"

His eyes glistened with frustrated tears, and his breathing was as erratic as his hearts. He blinked away the moisture in his eyes before it could fall, but her heart still broke for him. He carried around so much guilt, and refused to let go of a single transgression. This went far further than just letting her fall into that vat, but for now, this was a battle she could fight.

"I'm so sorry, Rose." The Doctor choked out the words. "I'm sorry I couldn't keep you safe. I promised. It was my job-"

"Stop. You don't get to do this to yourself. I slipped, Doctor. You want to blame me, or fate, or the universe? Fine. But you don't get to blame yourself. I know you promised to keep me safe, but it's not up to you to save me from every bruised knee or sprained ankle or vat of poisonous bath product. I chose this life. And you know what?" She paused, and looked at him steadily, convincingly. " I don't regret a single moment. Travelling with you? I love it. Monsters and sickness and evil bath products and all. Because I love travelling with you. I love…"

She pulled him into a tight hug before she could say anything stupid.

His arms stayed static or a few moments, and Rose was just about ready to pull back from the hug and try to fix what she'd said — what she'd almost said — when he drew his arms around her and hugged her back just as tightly.

She smiled into his shoulder as he burrowed his face in the crook of her neck. Then, in the smallest of voices, she heard him say,

"Me too, Rose Tyler. Me too."