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Nodus Tollens: n. the realization that the plot of your life doesn't make sense to you anymore—that although you thought you were following the arc of the story, you keep finding yourself immersed in passages you don't understand, that don't even seem to belong in the same genre.

Dark Side.

Chapter 1: Nodus Tollens. Part I.

'In the end, I let the windows get dirty.
I couldn't stand to see your absence through the glass.
And in the end, I learned to sleep with the light off,
So tired from giving space to shadows of the past.'

—To Build A House. Cosima.

Eternity can be tiring. Having lived for five hundred and thirty years, eternity is something Cassandra Woodhouse knows very well. She has lived in and visited all one-hundred-and-ninety-five countries in the world several times. She's made friends and lost them; she's made enemies and gotten rid of them. She has seen every member of her family be born, live, and die. She has fallen in love, hard, more than once. She's kept secrets. She's spread rumors. She has gone to higher education in five different countries. Most importantly, Cassandra Woodhouse has learned how to keep herself busy, entertained.

Still, some years, like this one, she finds herself bored out of her mind. She didn't think she would be returning to the United States of America until at least five years, but pressing responsibilities have forced her to. Stupid witch's code, she thinks, rolling her eyes as she switches lanes towards the exit leading out of the highway. She barely even practices magic anymore, knowing very well that being a vampire-witch hybrid is a very dangerous thing to be in this world, surely that should exempt her of having to take on a student, right? Emily Bennett, may she rot in Hell, doesn't seem to agree.

Cassandra sighs, flipping off the asshole currently beeping at her for not driving off the second the red light turns to green. Of all the places, of all the tiny, silly towns in this goddamned state of Virginia, why did she have to come to Mystic Falls? She avoided the town for the last one hundred and forty-five years like it was the plague.

WELCOME TO MYSTIC FALLS, VIRGINIA. POPULATION 6, 923. The big, green sign reads. God, that's small, she laments. Small towns are boring, there's absolutely nothing to do in them. It was the same reason Katherine and Cassandra had moved here oh-so-long-ago. Mystic Falls was tiny, isolated, and basically lost in the map. Perfect for their plans.

State of Virginia, America, eighteen-sixty-four.

Cassandra Woodhouse sat in the moving carriage across Emily Bennett, the dark-skinned handmaid who accompanied her and her friend towards their new temporary home. They were moving once more. It was becoming incredibly tiring. She glanced out the window. Nothing surrounded them except for miles and miles of thick forest. So different from New York, so boring.

"Katherine," Cassandra started without turning from the window. Her voice was as calm as the surface of a lake in a windless afternoon. "What is the exact reason we are moving here?" she asked politely, although what she really wanted was to rip Katherine's throat out. It wasn't fair. They had been having fun in New York.

"You know why," Katherine Pierce said for the fifth time since they had left Atlanta.

"Oh, that's right. Because you're scared of the big bad wolf," Cassandra replied back sarcastically. "Or big bad vampire." She clarified, enjoying her own jest at the brunette vampire.

Katherine and Cassandra faced each other. Their eyes met, brown clashing with green with more than just anger. Cassandra knew Katherine wanted her to look away first, to give in first. She would not.

"You knew what you were getting yourself into when you decided to follow me," Katherine said slowly.

Cassandra clenched her teeth at the comment. It wasn't like Katherine had given her much choice in the matter, and after so many years going anywhere else felt unnatural. Katherine was Cassandra's closest and oldest friend. They were practically family; not that she could trust Katherine completely, but she'd have to do. Cassandra was mad at her for having to move so often, though. Katherine was so terrified of Klaus and his people that every time she believed someone had a clue of their whereabouts, she'd run.

Cassandra was afraid of Klaus, too, of course. Even though she had been alive since the fifteenth century, even though she still had her magic, Klaus was still much more powerful than she was. Witches could not keep their powers once they turned but hers had somehow stuck around. She supposed it was her own punishment for all the things she had done as human, or maybe because she hadn't exactly been a servant of nature. It was a secret well kept, however, and only a few people knew. Being a hybrid was perilous. If Klaus found out, though... Cassandra shook herself internally and focused back into the situation at hand. She knew their plan had to be carried through, but it could have easily been done in the state of New York.

"But I was having so much fun back in Manhattan and then we had to go all the way down to Atlanta for this trip. I'm tired." Cassandra whined just like Katherine had taught her to, when she wanted people to excuse her bad behavior.

"Don't worry, we'll stay here longer. I promise." The other girl affirmed just as the carriage went to a halt and stopped in front of a beautifully white two-story house.

Outside the house stood two gentlemen, one looked younger than the other but not by much. Both men were breathtakingly handsome. Katherine looked at them as the door was opened and she climbed out, bowing politely at the young man standing before her and giving him her hand for him to kiss.

Cassandra's turn to descend the carriage came at the same time the young man said:

"You must be Miss Pierce."

The gentleman's voice was deep and a bit raspy, but it irradiated youth. Cassandra surmised he was around sixteen or seventeen years of age. So young and most likely about to be ruined by one Katherine Pierce. Cassandra had noticed the way the brunette vampire had eyed the man the moment she had gotten out of the carriage. Katherine Pierce had found herself a shiny new toy and, judging by the way the young man was gazing at her, Katherine would not have to convince him much. So, Cassandra simply stood to the side, not paying much attention to the conversation taking place beside her and focusing instead on her surroundings. Something caught her attention. Was that a labyrinth?

Damon Salvatore stood near his brother as Stefan welcomed the two women who would stay with them for the year. Damon would wait for Stefan to finish and then he would welcome the women and introduce himself to them. But for the time being, he'd study them. The girl standing to the side looked incredibly unhappy, which was understandable. The two young women had recently lost their entire family to a tragic fire. Still, he could not help but notice how beautiful she was. Her red hair was in an intricate up-do, partly covered by a white hat. Her lips were pursed as curious, sparkling green eyes travelled around the gardens. A handful of freckles were scattered across her nose and cheeks, like raindrops against a window, both light and dark in color. Damon frowned unnoticeably. Miss Pierce and Miss Woodhouse were as different as the moon and the sun. What was their relation again? Damon wondered. Distant cousins, he remembered with a small nod.

"Miss Woodhouse." Stefan bowed, snapping the redhead out of her studying of the garden. She turned to look at Damon's little brother.

"I'm Cassandra, Mr. Salvatore, please do call me that," she said, politely giving Stefan a smile.

Damon's stomach clenched at that smile. It wasn't that special, and he was almost positive that she was feigning it, but something about that smile had affected him greatly. Tearing his eyes quickly away from the redhead, he looked towards Miss Pierce and immediately forgot whatever it was Miss Woodhouse's smile had made him feel. For Miss Katherine was by far the most beautiful woman he had ever seen, with her dark brown curly hair and matching eyes, also an olive skin that suggested she had family in Europe.

Stepping forward he took Miss Pierce's hand and gave it a kiss as he said: "Miss Katherine, I'm Damon Salvatore, Stefan's older brother."

Katherine bowed before the other brother, who was as handsome as Stefan. As she met his blue eyes, Katherine allowed a very small smirk to play at her lips. Then Damon moved to the other girl and did the same, for some weird reason dreading his reaction to the redhead.

"It's a pleasure to meet you, Mr. Salvatore," Miss Woodhouse said.

"The pleasure's mine but, please, call me Damon." He answered, receiving a lovely smile from the girl. The clenching returned, this time accompanied by the increase of his pulse.

"Very well, then." Cassandra nodded. "But I insist you call me Cassandra." She tried as hard as she could not to giggle as she met Damon's eyes.

Present time, Mystic Falls.

Cassandra sighs as she gets out of her car, slamming the door a bit harder than she had intended. Renting a house that met her needs took longer than she would have wanted and now she's late. Except late doesn't even cover it. School is almost over for the day, and she knows she should have started on Monday and not today, but she wants to get this out of the way. The sooner she goes to school, pretends to be a teenager, and befriends the young Bennett witch, the sooner she can get out of this damned town. She wishes she could forget, somehow, about eighteen-sixty-four. She wishes she could forget about Mystic Falls. She wishes, more than anything, she could forget about Damon Salvatore.

She attracts the attention of every student as she walks, something not new to her. The boys are gawking at her, and her car. She fights the urge to roll her eyes. Have they truly never seen a Land Rover? Or a pretty girl, for that matter. The girls, though. The girls are glaring at her so furiously she suddenly gets a new surge of self-confidence. Cassandra is wearing a light pink A skirt, a white blouse, and some heels. Her long, red hair is to her left side in a tight fish-tailed braid, reaching her waist. Her make-up is soft and subtle. She looks lovely and sexy at the same time. Humans need to get a grip; it's not her fault she's hot.

Picking up her schedule at the school's office takes longer that she hoped it would. At this rate, she will have to come back on Monday. Finally, the fifty-year-old lady with a bird's nest for hair and lipstick stains in her teeth gives her the schedule. She makes her way to room 0.34, where History class takes place.

The second the door opens; the entire class looks up. She walks towards the teacher and hands him the slip with her information. The teacher, a young, thirty-something handsome man, seems surprised to have a new addition to his class. He grabs the slip from her hand and looks down at it, a barely noticeable frown in his face.

"Right, Cassandra Woodhouse, transferred from Anchorage, Alaska," he says as he reads the card. "Welcome to Mystic Falls, I'm Alaric Saltzman, your history teacher. Take a seat." Mr. Saltzman directs her to the only available seat, right behind the Doppelgänger.

That's not what makes Cassandra falter in her step. She knew the Doppelgänger lived in Mystic Falls, of course she'd been planning to avoid her, but it's not surprising. What is, is the fact that Stefan Salvatore is sitting on the seat next to the only available one. Stefan Salvatore, who fully believes her to be dead. Her dead heart skips a beat as she walks through the aisles of desks and swiftly slides into her seat.

Neither Stefan nor Cassandra pay attention to class. They're too busy staring at the other, Stefan openly and Cassandra out of the corner of her eye. She pretends to enjoy his shock. Last time Cassandra saw Stefan this human, he was dead, killed by his own father for trying to free Katherine. She never got to say goodbye. Cassandra fled Mystic Falls as fast as she could and, even though she kept an eye on both brothers over the years, as far as Stefan and Damon Salvatore are concerned Cassandra Woodhouse is as good as dead.

She's wanted to keep it that way for the last ninety years. Even that small bump in the road in the nineteen-twenties was something she hadn't planned. Stefan had forgotten all about her, courtesy of Klaus, of course, and she had lived life to the fullest after that. Yet, here they are. What happens if Stefan tells Damon? Is Damon in Mystic Falls, too? Goodness, are the two brothers even in speaking terms? She has no idea.

She's busy rooting the day she thought it'd be a good idea to not keep an eye out for the two brothers, sometime around '79, when the dismissive bell rings around the room. She bolts for the door as fast as she can, blurring the line between supernatural and human behavior. She knows it's no use, nothing she can do will stop Stefan from following her. Even if for some luck she escapes before he can confront her, she knows her fate is sealed: Stefan Salvatore will search for her now, until he gets the answers she knows he wants.

So, taking a cleansing breath in and masking her face into an expression of nonchalance and boredom, she walks to her designated locker, slowly opening it to push in all the heavy books and folders she is now in possession of. It's not been three minutes when the metal door slams without her wanting it to. Cassandra blinks and turns around, to her left, where Stefan stands with a frown so deep in his features she wonders if it'll ever come off.

"Stefan," Cassandra starts, green eyes roaming down his body. "Long time, no see." Her tone is neutral and unfeeling.

There's a beat of silence. Next to him, the Doppelgänger tenses all over. Her coffee brown eyes, just like Katherine's, are examining her closely in what Cassandra can only describe as fear. The thing that confuses her, though, is that the Doppelgänger, Elena Gilbert, she reminds herself, seems to have an inkling of recognition flashing through her face. As if she knows Cass.

"What are you doing here?" Stefan asks, ignoring her sentence.

Cassandra feels herself react to the question and stops herself from frowning. What are you doing here? How is that the first thing he has to say to her? Does he remember Chicago, then? No, that's impossible, Klaus made sure of that. Where's the 'I thought you were dead,' or the 'how can you be alive?'. She was even expecting a 'why haven't you contacted me before?' After all, they were friends, back in eighteen-sixty-four. Close friends.

"Well..." she smiles a bitter, borderline-fake smile, and pauses. Stefan seems to be on guard, tense, and his hand keeps tightening around Elena's. "I started a life here before, why not now?" Cassandra asks with a mocking tone.

With that, she finally turns to the brunette girl. This close, she realizes that while Elena is the exact physical copy of Katherine, their auras are completely different. Elena and Katherine are nothing alike, at least not yet. Elena still has, after all, some drop of Petrova blood. Now, the young teenager is squirming under Cassandra's gaze. Cassandra can practically smell the nervousness running through Elena's veins. In that moment, and probably out of pity, she makes the quick decision to be... kind.

"It's really nice to meet you, Elena." She smiles, genuinely this time.

Cassandra watches, amused, as Elena Gilbert's eyes widen in surprises. The human girl stares at the redheaded vampire, mouth almost agape. Cassandra knows Elena was expecting her to think she was Katherine. To be fair, it is quite surprising that Cassandra knows who Elena is but not the fact that Stefan Salvatore lives here now, or the fact he's obviously in love with the Doppelgänger. In love with his ex's lookalike? He clearly has issues.

Still extremely amused with that piece of information, Cassandra starts to walk away, relaxed. So far, this hasn't been that bad. She's barely taken two steps forward when Stefan's hand clamps down around her arm, forcefully. Elena jumps a little. Cassandra, however, simply looks down at the tight hold the young vampire has around her arm, and scoffs at the fact he's actually trying to inflict pain.

"Explain to me why you're here." Stefan nearly snarls.

Cassandra laughs like Stefan just told her the best joke in the world. In a way, he has. After all, Cassandra is three hundred and sixty-seven years older than him. She could take him down without him even noticing. Elena, however, finds the action extremely eerie.

"No, Stefan," Cassandra's hand goes to his wrist. She digs her nails into his skin hard enough to spring blood. Stefan has the decency to flinch almost unnoticeably. "Let me explain something to you. I'm not here to make your life miserable; I believe Katherine already did a pretty good goddamn job about that." Cassandra snaps at him, completely appalled.

Stefan looks at her, surprised, any form of his former hostility disappearing. She frees her arm from his hold, fed up with this conversation.

"So, you will continue to live your life with Elena, and I will continue to live mine in my new home." She shrugs, reaching forward, and wiping Stefan's blood off her fingers in Stefan's shirt. Then, after a moment of consideration and Stefan staring at her, she takes a step closer to him until there's only a few inches between them. "Easy it down on the human blood, will you, Stef? Wouldn't want you to lose control, now do we?" she whispers in his ear, too low for Elena to hear.

Satisfied with having the upper hand, just as she thought she would, Cassandra sends them both a smile and begins to walk away.

Elena watches Cassandra Woodhouse go, almost in awe of the exchange she just witnessed. She knows her name. Elena's heard it once, maybe twice, this past year. Mostly from Damon, which had made her believe this Cassandra person was probably not what she had been described to be. But now, Elena has no idea what to think. When Cassandra walked into History, she looked pretty normal, absolutely gorgeous, but human. Elena had chalked her sour furrowed lips up to just first day jitters. Clearly, she'd been wrong.

"Who is she?" Elena asks after a few seconds of nothing but stunned silence.

"Cassandra Woodhouse," Stefan says vaguely.

"I gathered that," Elena fights the urge to roll her eyes. "But how do you know her?" Elena insists.

Damon said she was a friend. The day her dinner for Stefan, and Bonnie, got crashed by Caroline and Damon. He brought her up in passing, before delving into an awkward conversation about Katherine that Elena still has etched to her mind. Stefan has mentioned her, too, once, in a tiny, clipped sentence Elena had made no sense of but that seemed to have resonated deeply within his brother: "Cassandra wouldn't." In front of her, her boyfriend sighs.

"She's Katherine's best friend, Elena." Stefan admitted. "They were so close, they pretended to be family when they lived with us."

He's thinking hard, Elena can easily see this. That is a surprise, even though Elena isn't sure why. The way they talked about her, Elena thought maybe Cassandra had been a friend from after they'd turned. Apparently not. After hearing how Katherine really is from Stefan, she's suddenly even more intimidated by the redheaded vampire.

"So, she is the one who was friends with you and Damon." Elena comments, somehow needing confirmation between this Cassandra and the one that has been talked about.

After all, the one that's been talked about, even if it has been only a few times, was always talked about with almost care, appreciation. The exchange Elena just saw, however, was filled with tension and contained anger.

"She was more than that, Elena." Stefan sighs, looking down. Seeing Cassandra after a century and half has opened a door Stefan thought had been well closed. He can only imagine what it'll do to his brother. "I've got to tell Damon."

Elena nods and kisses her boyfriend goodbye as he hurriedly leaves the building. Instead of going to her last class for the day as she should, Elena goes the other way around, towards where Cassandra went. She finds the redhead in the parking lot, slowly walking towards her car.

"Cassandra, wait!" Elena calls after her.

Elena sees the vampire stop and turn. She's suddenly hesitant. What is she going to say? Cassandra lifts and eyebrow, waiting patiently. Elena gets the hint and hurries towards her, a small, almost shy smile covering her face.

"I didn't think you'd stop." Elena explains once she reaches the redhead.

Cassandra considers her for a moment. Her green eyes, greener than Stefan's, which was something Elena didn't think possible, roam around Elena's face and body carefully. After a moment, Cassandra smiles the same kind, trusting smile Elena had received earlier.

"Why?" Cassandra asks. "As far as I know, if the most popular girl in school is talking to you, you stop."

Elena is surprised to see the girl is actually kidding with her. Is it because she's friends with Katherine? Does Cassandra think Elena is anything like her other friend? The hesitance returns.

"You're confusing me with Caroline." Elena shrugs, curiously wanting to know where this is going.

"Right, you're second in command now." Cassandra laughs.

Elena blinks. This girl is completely different from the cold, almost dangerous one that spoke with Stefan. There's something almost angelical to her laugh. It's haunting.

"How do you know so much?" Elena asks, having trouble masking her surprise.

The redheaded vampire shrugs like it's nothing.

"This school has a really good gossip system," is all the explanation Elena gets.

She doesn't trust it entirely. After all, Cassandra had only been here for a day. Silence surrounds them for minutes. Elena has no idea what else to say. She doesn't even know why she chased Cassandra down anymore. The redhead continues to look at her, patiently, but something in the back of her eyes shift and Elena knows she's getting impatient.

"What do you want to know?"

The question is unexpected, but Elena is shocked to see it's the right question to ask. She ran after her dying to know more of the story she couldn't help but feel Stefan kept fixing to his liking, the story Damon only talked about in fragments. She's so curious to know the truth of what happened. Surely Cassandra can give her an unbiased version of the story.

"How did you—I don't want—I mean it's not that I don't find your story interesting..." Elena stutters. Cassandra has seen right through her.

"Elena, it's fine." Cassandra lets her know. "I understand, really."

Elena smiles, relieved, but before she can delve into a full-on interrogation, the redhead is talking again:

"I'll tell you someday, but not today... or next week." she adds before the brunette can get any ideas.

Her tone isn't warning, it's easy and almost happy. Elena doesn't understand. How can she be this nice to her? Don't Cassandra and Stefan hate each other?

"I don't get it." Elena shakes her head, stunned. "Why are you so nice to me?"

Cassandra frowns. Her eyebrows scrunch upwards slightly, her mouth furrows. She's clearly thinking about something.

"You might be my oldest friend's lookalike, Elena." Cassandra begins. "But I can tell already you're nothing like her. And, if what I suspect is true, then I'm going to need a genuine, kind person to be my friend."

For a moment, Cassandra looks like she's feeling the deepest sadness Elena has ever witnessed. There's something about the way her eyes shine, like she's holding a secret nobody but she must keep, that makes a sting of both pity and dread hit Elena's stomach.

"But, why would you want me to be your friend if you clearly hate Stefan and Damon?" Elena demands, protective of her boyfriend and, heaven forbid, even his brother.

There's a beat. Cassandra looks at Elena like she just said the worst thing in this world imaginable. There's almost a glint of fear in her eyes.

"You—you—He's—wait," the redhead stutters, wide-eyed.

Elena watches her physically take a deep breath in, and she realizes that whatever reaction she just witnessed was not supposed to happen.

"Damon's here, too?" Cassandra asks, her tone back to the cool and collected one Elena knows.

"Wherever Stefan goes, Damon follows," Elena says, not helping the venom that laces her voice.

The vampire's eyes narrow just a fraction. Elena doesn't pay attention to that, though, she's too busy thinking. Clearly, Stefan and Damon being here was not part of whatever plan Cassandra had.

"You didn't know they were here." It's not a question; it's a statement.

"No, I didn't." Cassandra shrugs. She mumbles something underneath her breath, too low for Elena's human ears to catch on. "I saw on the newspaper there's a town party today?" Cassandra asks, changing the subject.

"Yeah." Elena nods, holding tight to her school bag. "It's Founder's Day party. You should come! It'll be fun, and you'd get to be introduced to the Mayor and everyone else-you know, start fresh and all that." She explains to Cass.

"Sure, why not?" Cassandra shrugs. "I mean, I went to the first one."

Elena laughs, and Cassandra replies with a smile of her own. Quickly, and afterwards she thinks it might have been too quickly, Elena gives who she hopes is her new friend her phone number and tells Cassandra she'll see her at the Founder's Hall.

"Bye, Elena."

With that, the two women part ways.

Damon Salvatore lies lazily on the couch, the Boarding House's extensive library around him. He nurses a glass of bourbon, thinking hard. These past few weeks have not been the best for him. He's hurt and annoyed and, mostly, angry. He wasn't even supposed to be here anymore. The only reason he came to Mystic Falls in the first place was to free... to free that bitch. But That Bitch wasn't even in Mystic Falls to begin with.

Damon can, right at this moment, go anywhere he wants. And yet, he's still here. Stefan is struggling with his urges for human blood, John Gilbert knows a bit too much for his liking, and the remaining tomb vampires are still roaming around town as a threat to him and his brother and Elena. He rolls his eyes at himself. He's not supposed to care.

Damon hears the front door open and close, but he doesn't bother to go check who it is. With his luck, it's Pearl again, this time feeling like ripping out his kidney. Actually, with his luck, it's probably That Bitch herself. It turns out to be Stefan, looking troubled.

"What's got your panties in a twist, brother?" Damon teases, taking a sip from his glass.

Stefan ignores the jab, instead staring at his brother for a serious moment.

"Cassandra is alive."

Damon's smirk fades away. Cassandra Woodhouse is dead. That is a fact Damon has known to be true for 145 years. It hurt him like hell, at the beginning, until he'd turn his humanity off so many times the hurt just disappeared. Still, whenever the chance to open the damned tomb arose, Cassandra would filter into his mind. He always hoped maybe she was down there, too. That hope was destroyed when he opened the tomb to find it empty of the only people he cared about. No lover and no best friend. And now, here is Stefan, lying about Cassandra.

"Don't joke about that, Stef." Damon mock-scolds him, even if he feels like defenestrating him.

"I'm not joking," Stefan shakes his head, crossing his arms over his chest. "She was at school today, like nothing had happened. She knows more than she lets on, though, I can tell." Stefan starts pacing back and forth.

What if the redhead is a threat to Elena? It can't be a coincidence that she shows up right now, when they're in the middle of a major threat. They've been dealing with rogue vampires left and right and Stefan knows how volatile Cassandra is. He remembers what it was like when he lived under Katherine's and Cassandra's reign. They can't have her pretending to be an angel but turning into a murderous demon when she feels like it. Stefan is so engrossed in his thinking, he almost misses Damon walking out the room.

"Woah, no." Stefan calls. "Where are you going?"

"We are visiting her." Damon corrects as he walks out the library. "If she truly is here."

A/N (PLEASE READ, THANKS):

Hello! Well, I can honestly say it has been years since I last published anything here.

If you clicked on this story because you love Damon Salvatore, and TVD, welcome! Thank you so much for clicking on this story and reading it, it means a lot to me. I would love to hear your thoughts!

For those of you who ended up here because you follow me, and received an email notification telling you I'm posting again you probably recognize this story. Yes, indeed, this is Dark Side but with much better writing, much better understanding of the story, with a better-written Cassandra Woodhouse, and most importantly now that TVD is sadly over, with a writer that now has a perfect understanding of all plots with which I can play with. That being said, this is not exactly the same story! So, I do suggest you read it all over again!

This story will eventually have some warnings, but I will let you know before hand if we're approaching sensible content. This story is also available on Wattpad, same username, same title.

Anyway, see you soon!

Titieli.

UPDATED: 15/01/2020.