A/N: WARNING: HERE BE TENTACLES, GOING IN ALL THE NAUGHTY PLACES. YOU HAVE BEEN WARNED.

Chapter 1: What Lays Beneath

If you asked Anna Nomic to describe her life as succinctly as possible, she would most likely call it a "bumpy road".

She would always try to focus on the good, which came abundantly enough. For as long as Anna could remember, she had lived in a picturesque suburban home by the beach side, with pure white walls and a slate roof that always managed to look pristine. It was rare that Anna didn't get something she asked for, within reason of course (getting her own castle would have to wait). Her parents and especially her sister Elsa cared for her through thick and thin. She even had a few friends that had managed to stick by her throughout all the 'difficulties'. Which unfortunately lead her to the bad.

For one other thing also plagued Anna for as long as she could remember. Some kind of strange growth had been attached to her middle-back for what seemed to be her entire childhood. After all that time though, Anna couldn't even be certain what it was. Some kind of bad rash? No, those went away over time. An infection? Those got worse over time. This one just stayed steady, seemed only to slowly expand along with Anna herself.

It was quite fortunate that for Anna, it was difficult to see. Because it was damn difficult to look at. Most of the time, it was a mess of rough, coarse brown and red. There was even the occasional time there looked to be green boils growing outward. The first time Anna found one, she became convinced that it was alive. It took a good few weeks for her family to calm her down and assure her they could get through this.

To their credit, her parents were steadfastly understanding of the difficulties Anna faced. Except, as Anna started to notice later on, in explaining the nature of Anna's condition. She could only remember visiting a doctor about her condition once. As they left, neither mum or dad would tell her the diagnosis. Only that everything would be fine. That, and she needed to take special medicine once a week. Anna did not care for the unsavoury pills and liquids at the best of times, but this stuff in particular tasted as though it was scooped out of the bottom of a pond.

The worst part was without a doubt this endless need for them to keep Anna at arm's length. The only time Anna was allowed out of sight for more than an hour was to attend school, after which it was a journey straight home. No leaving to hang out with her friends, and definitely no sleepovers, even at her own house. Hell, she couldn't even remember them going on a family trip for more than a day, let alone leaving the country.

By all rights, this should have gotten under Anna's skin sooner or later. Especially as she got older, and her questions, no matter how persistent, were deflected. It got just that much harder for them each time Anna asked. Each time she was forced to swallow that vile liquid. Anna was getting older. All she wanted was the truth. Was that so much to ask? It seemed only a matter of time. Surely her parents would open up.

Only they never got a chance. It should have been a warm summer's evening like any other. With Elsa reaching adulthood, their parents were finally able to enjoy some time with each other. A nice, romantic cruise. Only a few days. Those words haunting Anna's mind as they found out their parents would never return. Whatever secrets they might have been keeping, they took to their graves.

This left the two sisters with a house too large for just the two of them, and far too expensive to sustain for more than a year or so without a reliable source of income. Having reached the age of majority, Elsa took it into her own hands to relocate both of them across the country. Much nearer to where Elsa planned to begin her higher education. Not to mention away from the endless sea. Both of them seemed to quietly agree that they needed as few reminders as possible while the grief was still fresh.

It would have been nice if life simply went on in their new, more modest house. Anna had accepted transferring to a new school, while Elsa sunk her teeth into her degree in architecture. While Anna tried to keep pushing forward with a smile on her face, settling into a new place is never easy, especially with a unique condition. Children can be cruel enough, but teenagers seem to push the limits of how petty and vindictive someone can be. Sure, Anna could conceal the growth, but not the curfew she could no longer bring herself to break. That meant none of the good parties. Not to mention one or two rumours started to circulate.

Anna refused to let it get to her. Literally. When that would result the thing on her back would start to get especially uncomfortable. When asked about it, Elsa eventually came up with the idea that it was most likely stress. With that, she would once again give Anna the encouraging words her parents used to. They were still in this together. Weren't they?

That look. The same guilty, distant look Anna noticed from her parents. Elsa started to show it as well. She might have been a little better at hiding it, but it wasn't quite enough. There was no way of knowing if she knew as much as their mother and father, but she clearly knew something. There could be no doubt. Each evasion became slightly harder than the last. Slightly more painful. Even after all this, was Anna not worth the truth to her?

Instead of healing the deep wounds, time only served to drive them further apart. There was no shouting or even what could be called rudeness, just this small gulf between them. Elsa spent more and more time locked away in her room. Deep down, Anna understood. Or at least, she really wanted to. Elsa was on course complete her degree with the highest possible honours, something that required all the undivided attention it could get. Yet, that must have left her with some free time. If she did have any, there was none to spare for Anna, save to make sure she was still taking her "medicine". Any other time, Elsa was headed straight to her room, always with a rather bulky bag of books. There were even times when Anna could see a strange, flickering blue light from under Elsa's door. No noises, just the light.

Anna would always end up shaking her head. She couldn't let the stress get to her again. Maybe one of her old friends would be online tonight. It wasn't as though she had much else to do.

This all came to a head when Anna's final year of school began to draw to a close, and it came her turn to apply for college. Anna found plenty of places where she could study psychology. A chance to finally move away, spread her wings and breathe for once. Show Elsa she was more than capable of taking care of herself. Maybe some distance from each other would help them heal the undeniable rift between them. Go back to just being sisters. Anna would like that.

So of course, Elsa was having none of that. When she brought it up over dinner, Elsa kept gently suggesting that Anna choose a place closer to home. Even if she didn't say it, it was obvious that Elsa didn't want Anna moving away.

"Why don't you want me choosing where I go? You got to choose, didn't you?" Anna asked, pushing back the brochure she was given.

Elsa sighed, apparently unmoved. "I needed all the resources and help to get a good enough degree. Besides, we needed to move at the time anyway." Elsa shook her head. "We still have money to consider as well. At least until I can get a steady job."

Anna seethed. Excuses. "Oh, so you need top of the line. But when it comes to my turn, we have to pinch pennies? It's not like I'm smart enough to get a good degree, is it? I can just go to any old shack that calls itself a college. Just as long as you can have me at arm's length!" That wasn't Anna. Yet it all came out anyway. Maybe it was thirteen years of being told to just trust her family when they couldn't even do the same for me.

"Anna, that's not-" Elsa started to stammer. "What if you condition gets worse?"

"Stop treating me like I'm going to explode!" Anna thundered. "All this time. All these years and nothing has happened. Nothing! Maybe if you just told me what the deal is with this rash, or growth, or infection, or whatever. But no! Just look away, run back to you room once you've made me drink my liquid crap." Anna could feel her eyes welling up. "This isn't fair. Just tell me the truth, Elsa! I won't get mad at you, I promise. Maybe I can help."

"I can't do that, Anna." There was a clear mask of cold authority over those words. "I- I just can't."

"What did I ever do to you?" Anna bolted up fast enough to knock her chair down, before storming off. She was far too furious to continue. At both of them.

Anna let herself fall face-first onto her bed. Her brass, double bed. Whenever she would get mad, Anna would remind herself of all the nice things she still had. The desk fitted with her own computer. The closet full of almost all the clothes she'd ever asked for. The computer sitting on the desk. There were even a couple of games consoles she couldn't remember the last time she'd played. They'd even managed to add the vibrant green floral wallpaper Anna wanted.

It was becoming all too clear now that this was little more than a gilded cage for her. For whatever reason, her parents and now Elsa were obsessed with keeping her close her whole life. All over some kind of growth on her back, which Anna could barely count the number of things she knew about for sure on one hand.

Was it wrong of Anna to explode at Elsa like that? There was probably going to come a point where she couldn't hold her anger back. Did Elsa really not trust her? Maybe there was some kind of promise she had made with her parents before- before-

"Fuck!" Anna felt so confused. Why did her family unconditionally love her for everything except this one, stupid thing? If it wasn't for this one little health problem everything would be fine. There would be no need to coddle her or make her drink that vile concoction. She could have friends like a normal person. More importantly, her and Elsa could be family like normal people. How did Anna even get the thing on her back to begin with? She could remember all the way back about the age of five, when she was sure it was there. Then- then.

Gah. Anna clutched her forehead. Why couldn't she remember? Was there something Anna had done? Was this all her fault? That would certainly explain the paranoia that her family treated her with. Though it left the question of what was wrong with her wide open. Not something that could infect anyone else, Anna knew that much. Stranger still, it wasn't something any kind of doctor could help with. If Anna had once thought of cutting the growth off, then Elsa and her parents must have done as well. The more she tried to think this through, the less sense it ending up making.

All the while, another, darker thought crept through the back of Anna's mind. Always whispering back to her the moment her thoughts hit another dead end:

Run away.

It wasn't too hard to push back against. Even to Anna, it was a stupid idea. She had practically nothing in the way of money. Thanks to her rather stunted social life, there was nowhere for her to go, either. Not to mention the effect it would have on Elsa. Deep down, Elsa must have loved her still. They only had each other. It was easy to forget Elsa lost her parents as well sometimes.

Somewhere in the storm of emotions and confusion, a plan was starting to form, with the help of one or two other pieces of information. First of all, Anna's eighteenth birthday was barely a couple of weeks away. If nothing else, she wouldn't simply be a runaway child any longer. More importantly, their parents left their money to both of them. Elsa was the only one old enough to access it. With one modest withdrawal, Anna could find somewhere cheap to lay low for a night or two. Not too long. Just long enough that Elsa wouldn't take Anna's presence for granted any longer.

Anna would an adult soon. She would be damned if Elsa wasn't going to treat her like one. Even if she had to play a little dirty.

The plan quietly continued for the proceeding days. Even if that plan mostly consisted of Anna waiting for things to fall into place. The more normal everything seemed, the less likely Elsa was to realise something was up. If anything, it was Elsa who seemed rather suspicious as the days wore on; she didn't seem to hold Anna's outburst against her. In fact, she didn't seem to acknowledge it once. For a fleeting moment, Anna's plan was that much more difficult to justify. Things quickly returned to the status quo, with Elsa retreating back to her room more than ever. Perhaps she didn't have the time to get angry now.

As the days drew ever closer, Anna's nerves frayed a little more with each day, and her certainty about her plan continued to wane. She wanted something- anything from Elsa that could give her an excuse to turn back. Forget about all of this.

None came.

With a heavy, yet still divided heart, Anna devised a new plan. One almost definitely more desperate and foolhardy than the last. She was going to sneak into Elsa's room. Ever since they moved together, the door to Elsa's room was kept under lock and key. That wasn't normal for family members. Was it? The must have been something that revealed the truth, even when Elsa refused to. Whether she was keeping something from Anna for her own benefit or trying to protect Anna from some terrible truth, Anna only wanted to know.

Since their apartment was on the fourth floor, the door was the only remaining option. That meant Anna would need some way past the lock. Picking the lock was out of the question. Anna would just have to think on her feet for this one.

Once again, the sisters sat together quietly around the corner from each other at the dinner table. This was it. The big day. There were a few other things Anna had put into place, but most importantly she successfully withdrew the money. There was quite a lot more left there than Anna imagined. We still have money to consider indeed. Anna could have studied at the same place as Elsa if she could just scrape together the course credits. Not that Anna could bring it up. Maybe something to consider for her long-distance call.

Right now, Anna's least favourite part of the week sat in front of her. Why wasn't there anything she could do about it up to now? Her family had insisted she wasn't allowed to have it sweetened. No amount of thirst or even spicy food could make it taste anything resembling good. Just something she had to do. What was this supposed medicine even for, anyway? As usual, her family explained it was for her condition, but quickly side-stepped away from explaining what her condition was, or how drinking this helped.

Here goes. Taking one quick glance at Elsa, Anna picked up the bottle and threw the whole thing back as fast as she could. Even as an adult, holding the medicine in her mouth for more than a couple of seconds was more than her gag reflex could handle. With a slightly overblown shudder, she knocked the glass vial on the table. Elsa continued to eat as usual. She'd done it.

"Oh, Anna?" Anna suddenly froze, turning slowly to Elsa. "Could you help me out with something later? I need to take a bath, I'll be back in an hour or so."

Anna took a shallow breath. "Uh, yeah. Sure." What? That was it? How many eighteenth birthdays did Anna get to have? Not even so much as a happy birthday? Even after things got more difficult between them, Elsa never forgot. Apparently, if anything, this was a day to ask a favour from Anna.

Stay strong, Anna. This might have been an icicle to the heart, but at the same time it was a golden opportunity. A bath meant Elsa would be out of her room for a few minutes at least. Now the only thing to worry about was that damned door.

Anna finished dealing with the dishes and the medicine bottle just in time as she started to hear the sound of rushing water. Moving quickly but carefully down the hall, Anna saw the open bathroom door, along with a moving flicking back and forth. More importantly, the door to Elsa's room was ever so slightly ajar.

Not yet. This only had to fail once, then Elsa would be far more cautious. Her sister would be back in about a minute or so to properly get ready for her bath. Anna briefly considered the possibility of slipping inside and hiding somewhere until she had more time to search. Too risky. There was too much Anna simply didn't know. All she could be sure about was the door itself. Anna reached into her pocket. This would take some fine handiwork.

One minute, down to the second. Just enough time not only to pull away, but act natural. Anna crossed paths with her sister as she slipped into her own room, having to remind herself how to walk like a normal person. This could still go very wrong. Elsa was probably focused on bathing right now, but she could still happen to notice. She waited, and waited. It seems her fears didn't come to pass.

Click. The echo of the bathroom door shook Anna up. She was starting to shake. There was an uneasy feeling, which the growth wasn't helping much with. If she didn't know better, she would swear it could feel her tension. It was about a minute before Anna could get up. Elsa wasn't the kind of person to go back for something she'd forgotten, but you could never be too sure.

There it stood. The door between Anna and what she could only hope was the truth. She couldn't hesitate. She knew she couldn't hesitate. Yet, here she stood. No noise from the bathroom. Time was wasting. Anna grabbed the handle, and prayed.

There! The door came open. It worked. A rather simple trick, really. Rather than using a separate bolt to stop the door from opening, the lock stopped the door handle from turning. So, the simplest thing to do was place tape over the lock that was in place in just the right way. Too much, and the door wouldn't click shut. Too little, and the it wouldn't open regardless, and the whole effort would be wasted. Not bad, considering Anna only had one shot.

Anna slipped through the door, pushing it closed and fumbling around for the light switch. Really, she should have taken a light of her own. If Elsa happened to see light coming from under the door-

Not the time! With a few precious seconds wasted, Anna located the switch. The room was quite a bit to take in, even though it was only a small fraction larger than Anna's The walls were painted a cool blue, just a hint brighter than navy. If that was Elsa's choice, she must have done all the work herself. There was a large double bed and wardrobe both made from darkened wood. No surprise there. What did catch Anna's attention was the black desk built into the corner. It was engulfed in all kinds of books and papers. There were a number of printed documents and paperback textbooks, which were to be expected. Then there were what looked to be ancient tomes, and what looked like parchment. What was Elsa even studying? Renaissance style buildings? When Anna risked a look down, that was when her heart stopped.

A summoning circle. At least, that was what she thought it was called. Chalked onto the floor in pure white against the almost black floor. How had Anna not noticed? More importantly, what the hell was Elsa doing? On closer inspection, the circle was just large enough for Anna to stand inside, and was a pair of circles with a number of bizarre symbols between them. Anna stomach started to lurch, and not because her dinner was disagreeing with her. Several ideas about Elsa's intentions surfaced, all of which were far too- heinous to be believed. This can't have been what she wanted of Anna later, could it? She needed something conclusive.

Buried underneath the mass of literature there was a monitor on the desk. Anna switched it on. Password locked. No dice. Apparently the locked door wasn't enough. There was no time to guess what password Elsa might use, either. Her only chance now was to find something written down. Something that could stop raising questions and start answering them. The thick, deep red tome on the floor looked promising. Even more so when the circle on the cover matched the one etched onto the floor exactly. Handling the cover with the utmost of care, Anna looked at the first page covered in text. It was definitely written in English, but difficult to make out. Nine years ago, Anna was terrible with cursive. Now, well, she was still terrible. Slowly, the words started to make sense.

To truly understand the dynamics of extraplanar beings, one must discard any previous notions of thought and form. Mind, and matter-

Anna scratched her head. What the what? Reading this was already difficult enough. Understanding it was another thing entirely. Would there be anything Anna could take without Elsa noticing? It was only a matter of time before-

"Anna." She froze, like a deer in the headlights. Elsa stood at the door, just a simple bath towel to protect her modesty, and a small piece of tape on her left hand. "Did you really think you could use the trick I taught you?"

There was nothing Anna could say, which was just as well considered her brain appeared to have encountered an error. In the end, it was somehow her that ended up being caught with the smoking gun, not Elsa. Anna stepped back, clutching her arms, until she bumped into the desk. "I- I-"

Elsa sighed. "It started when I got a call from the bank about some unusual activity. It didn't take me long to remember that you had access now. I knew I needed to keep a close eye and what you were doing from then on." Elsa gave a rather coarse sigh. "Anna, why couldn't you have waited?"

"Wait for what? You to tie me to the floor and sacrifice me to some extraplanar whatever? To banish me to another realm?" Anna took a pair of rather aggressive steps forward. She felt the back growth start to burn up. Not that it stopped her. "Or maybe you'd rather live in a world of make-believe instead of with me-"

"That's enough!" Elsa ordered. Even amidst Anna's seemingly crazy, desperate outbursts Elsa managed to retain her calm authority. "Anna, I'm sorry. This isn't how I hoped this would go."

"Well- really? You didn't tell me anything in so long. And I thought- I dunno, I just wanted to know why!" Anna couldn't quite bring herself to look Elsa in the eyes.

Elsa nodded. "It's true. Looking back, it's obvious I took your trust for granted. I just wish you waited one more day. You never could be stopped once you would set your mind to something."

Anna unclenched her fists, and tried to ignore the discomfort that was still growing in her back. Elsa was talking like- a sister? Maybe this wasn't such a bad idea after all. "So, uh, what is all this, anyway? You don't seriously believe in magic, do you?"

"I do." With those words, Elsa gave a flick of her wrist, and the circle in the middle of the room erupted into bright blue flames, burning only a few inches off the floor, but steadily nonetheless. Without anything to burn. "Because it's real."

"Whoa!" Anna flinched. "Fire! Fire?" The carpet didn't seem to be burning up as a result. If anything, the flames were cold. "Is that- no."

"That's only the beginning, Anna." When Anna looked up to Elsa's face, there seemed to be an almost otherworldly blue glow reflecting from the flames. With another movement of her hand, Elsa dispelling the blue fire. "So here's what I'm going to do. I'll tell you the whole truth. All of it, right from the beginning. But on two conditions."

"Uh, well, okay." Anna was trying to stop her head from spinning. Not to mention her back was really starting to act up. She probably wouldn't be able to hide it much longer at this rate.

"First all, you have to believe everything I say. Or at least try to. I promise you everything I say is real." Anna nodded. That part seemed simple enough. "Second, you have to tell me the truth as well. Own up to what you were doing."

Anna managed a second nod, this one a bit slower. It was so much more embarrassing, now she happened to be caught so easily. "Yeah, alright."

"Alright. First of all, you planned on running away, didn't you?" That question was hardly a surprise, given everything else she figured out already. Though it wasn't spoken as harshly as she expected.

"Yeah, yeah. But only for a couple of days, alright. I thought maybe if I suddenly left, you would stop avoiding me and tell me the truth." Not really the best plan to be honest, considering there was no fallback for if Elsa refused.

"Even after-" Elsa shook her head. "Alright, second question. You didn't drink your medicine, did you?"

Anna shook her head, while leaning forward in a vain attempt to find some relief from her back. "Wait, what? You were right there, Elsa. You saw me drink it!"

"I saw you drink something," Elsa corrected. Before producing a glass bottle from under the towel. "Then, I happened to find this in your room. I take it by the shade your face turned that's not a coincidence."

Damn it all. It had taken Anna seventeen tries to get just the right colour and thickness to pass it off for the real, horrid thing. Too bad she couldn't fake the disgust that came with it. "Fine, I'll drink it," she grumbled. Suddenly, she had to clutch her back. It was getting too much to bear. Any more, and she felt it might burst.

"No, not yet. There's something you need to see for yourself." Elsa suddenly looked away.

"See wha- GAAAAAH!" Anna cried out and her back really did seem to explode. Or rather, something erupted out of it. Several somethings. When the pain was finally starting to subside, Anna realised she had taken up a fetal position on the floor. There also seemed to a cold breeze hitting her back. Dusting herself off, Anna reached back and found-.

Something warm, fleshy and slender. She almost didn't want to look, yet she felt compelled to see how deep this went. Anna looked right, and found two long tendrils reaching around her from her back. Then, she looked left and found two more. They were a deep, dark green and almost seemed translucent. Turning around confirmed Anna's worst fears: they were attached to her. No, they were a part of her.

"Elsa," Anna begged, eyes watered. "What- what am I? Am I even human? Am I even your sister?"

Elsa couldn't nod fast enough. "Yes, Anna. You're both, and you always will be. But- something happened. A long time ago. Let me start from the beginning."