A/N: Very excited to be writing this story! Some key things to note before we get started: this is an AU fanfiction (obviously). This AU entails that Harry was 5 when his parents were killed, he lives with Sirius with a little sister, and Voldemort was killed during the night of Lily and James' death. I don't normally do these notes at the beginning of stories, but it is important to note that this will be mostly light-hearted. A little angst never hurts anyone! Lastly, if you have the time, please review! I'm going to be writing ahead - so give me the motivation to upload the chapters at a fast rate! Criticism is more than welcome.

DISCLAIMER: I do not own the contents of Harry Potter. I do, however, own this story's *ridiculous* plot.

"You are my best friend as well as my lover, and I do not know which sid of you I enjoy the most. I treasure each side, just as I have treasured our life together." - Nicholas Sparks, The Notebook

The Potter and Granger Rivalry

Three Years Ago

"Sirius! Don't wake them!"

There, lying in front of Sirius Black - godfather and guardian of Harry James Potter, was a sight that could befuddle, and warm even the most harrowed soul.

Helen Granger scowled at Sirius, as well as the cup of ice-cold water he hovered over the two unsuspecting kids. "For all the talk you claim regarding the inevitability of their 'future relationship,' disrupting this moment would not be in your best interest," Helen whispered, closing in on the scene. The picture before her filled her heart with warmth.

The couch, in front of a dimly-lit Christmas tree, was occupied by the two young teens. Hermione was on the outside, facing the tree, while Harry's right arm draped lazily around her waist, holding the girl to his front. His chin rested upon the crown of her head and was partnered with an unconscious grin that explicitly depicted unadulterated joy.

Glancing at her daughter, Helen had a strong urge to fetch her camera from upstairs. Hermione, prior to Hogwarts, was reclusive due to her school-life and thus held an affinity for everything independent. It was part of what made her daughter so special - an unparalleled motivation, and quench for knowledge. Yet, this made little-to-no room for the social department. How that changed.

Helen and her husband Mike breathed a sigh of relief upon receiving their first card from Hogwarts, explaining that she made a friend named Harry Potter. Over the years, the boy held a piece of Helen's heart - so much so that seeing her daughter being practically spooned by him didn't provoke the protective-mother-monster inside of her. Part of it was due to Helen's relationship with the boy, but the crux of it was simply that Hermione never seemed so happy before his arrival in her life.

The girl in question held Harry's hand above her waist and was wearing a smile that resembled the unequivocal happiness that stemmed from her nearly 3-year friendship.

Careful not to wake them, Helen draped a quilt over the two, all the meanwhile glaring at Sirius's sly expression, still holding the glass of water in his hand.

"I'll give it four years."

Helen was slightly taken back. "Really? I thought you were so adamant that they would get together sooner rather than later."

"Four years 'till a proposal," Sirius replied, grinning at the two.

Present Day

Harry Potter was the biggest asshole to ever walk the earth. This statement, Hermione thought to herself, is axiomatic - it is simply an objective truth. Sure, there could be deranged psychopaths in the world, like the deceased lord Voldemort, hell-bent on maximizing human suffering. There are also cheaters, violators, bigots, and those who walked on the left side of the corridors (seriously, who does that?). None of those people, however, are even in contention with the sheer level of asshole-ness Harry James Potter so expertly flaunts on a day-to-day basis.

Hermione liked to think of herself as a cool, calculating archetype. She takes pride in keeping her cool, much to the contrast of her fellow Gryffindor peers. She viewed the world through a lens of logic, and reasoning, but still kept her virtue with her at all times. Only one individual could make her lose all semblance of her own personhood. Said person was standing right beside her, with an increasingly punchable smirk on his face.

"This, first years, is the short-cut to Gryffindor tower," Harry announced, beckoning the awe-struck first-years, and an increasingly angry Hermione, towards the corridor that Hufflepuffs traditionally use. "Now, if you're ever in a pinch like me, or just want to arrive at the tower two minutes before other chaps from the Great Hall, this is the fastest route back!"

Hermione could feel her self-control draining from her conscious after every word Harry delivered to the first-years. Of course, the boy who lived had their sole attention, with every sentence spoken taken in reverence. Not only was he, a fellow prefect - a role-model position for all the underclassmen - blatantly endorsing misconduct, but she couldn't argue or scold him! What impression would that leave on the first-years? Her patience and will to remain passive, however, nearly dwindled entirely after seeing his sadistic smirk at her dismay. Luckily, they approached the Painted Lady's portrait without any other harmful commentary.

Much to Hermione's annoyance, Harry crouched down, urging the first-years to follow the action with his hands. With feigned seriousness, Harry clasped his hands together. "Now, I don't want to see any of you out past hours," he paused, that smirk creeping on his lips again. "Unless of course, someone needed to mess with a Slytherin. Then I'm sure we'll be more than willing to leave a blind eye," he said, winking at the crouched group.

The bastard.

Just about every first-year immediately erupted with laughter, as if what Harry said was the pinnacle of comedy, and the funniest thing they have ever heard.

Right as she was about to launch herself into yet another public argument with Harry, she noticed a girl in the back, shaking her head with disapproval along with a roll of her eyes. Maybe there is some hope for the future of our house. The girl had brown curls, like herself, alongside startling green eyes, glimmering with what seemed to be an annoyance for Harry. In her right hand, was a novel Hermione would recognize any day of the week: Hogwarts: A history. I like her already, she fondly thought to herself. The girl seemed eerily familiar, but Hermione didn't pay any additional thought.

Hermione hastily went over the dormitories to the first-years, along with the rules and guidelines that came with them, aiming to prevent any more of Harry's incessant hooligan propaganda. After they all went to their dormitories, the common room was emptied with her fellow 6th-year friends and classmates, as well as Harry.

Almost immediately, the conversations concurred in the room abruptly dissipated, having noticed the two in the same room with each other. It was a mutual agreement, dated from the beginning of their fourth year, that an enclosed room could simply not house both Hermione and Harry. It was even listed on the common room's bulletin board, right alongside the other 8 'commandments' that ought to be strictly followed. Of course, the seven other commandments were added by herself, not wanting her relationship with Harry to be the sole rule on the board. Granger and Potter are not to be allowed in the same room with one another; if they must, then a minimum of 25 feet of separation must be exhibited.

Yeah, it was that bad.

Harry stiffened once Hermione put her left hand on her hip. This was perhaps the most telling sign of a Potter-Granger dispute. Harry's eyes visibly darkened a shade - another common sign. Just as Hermione was going to let him have a piece of her mind, Dean's shout from the back table stopped her, as well as Harry, from speaking.

"Oi! 25 feet!" Dean yelled, earning a few chuckles amongst the table.

Deciding that it was better to swallow her anger than it was to launch herself into another lengthy argument with him, Hermione briskly walked towards the table containing her four closest friends.

"That's what I thought, Granger."

That did it. Like a fuse suddenly lit, Hermione turned around, hand pointed, but was ultimately forcibly pulled to sit down by Luna. She gave Hermione her signature smile. "He's not worth it," she said, resulting in a murmur of agreements among the table. Hermione reluctantly agreed and pulled her potion's textbook and parchment out of her bag, not before sporting a glare over in Potter's direction, only to be met with another smirk.

"Say, Dean," Nevil grinned, shuffling his playing cards for another round, "do you think I would be allowed to change my prediction in the 'Weasley Granger-Potter' betting pool?"

Dean shook his head ruefully. "I tried last year after the Christmas Incident. Lost 10 galleons that year," Dean replied, wincing a bit at Hermione's glare.

"Honestly, no one is ever going to claim the pot," Hermione muttered. "The day that Harry and I reconcile is the day that the laws of the universe cease to exist. It's never going to happen."

Ginny, seeing this as the prime opportunity, nudged Luna and glanced meaningfully at Hermione. After a few moments of what was presumably internal debate, Luna nodded in agreement. "Hermione?" she started pensively, "will you tell us what caused you and Harry to… despise each other after being so close?"

Hermione instantly froze. Truth be told, she rarely pondered the 'what-ifs', and the 'whys' of her previous companionship with Harry. What normally filled her head, was what took its place: the infamous Potter and Granger rivalry.

It was, perhaps, one of the most discussed topics among Hogwarts - alongside Quidditch, petty relationship rumors, and classwork. It started off with animosity at the start of their fourth year, strictly by Harry's part. Contemptful glares, 'accidental' pushes in the hallway, and a refusal to speak with her among any circumstances. Very quickly, this hostility morphed into a two-sided relationship. At any moment, the two would engage in arguments in class so heated, that the professors quickly learned to place each other on the opposite sides of classes to nullify the tension.

After a few months, they had begun competing against each other in nearly everything, in an attempt to get an upper-edge on whatever petty argument awaited them. Thus was the beginning of the 2-year rivalry between them.

Hermione didn't dwell on the pain she felt her fourth year - the loneliness that consumed every fiber of her being. She didn't dwell on the many nights she spent crying, instead of sleeping, which effectively rendered her an insomniac. Most importantly, she didn't dwell on the sheer betrayal that pained her chest. Best friends for three years. Inseparable was the word used to describe them, both by students and teachers alike. No, it didn't do any good thinking about the hardest year of her life.

Looking up, she saw everyone's head eagerly facing her, awaiting a response. It was a question that must have been asked thousands of times, with thousands of replies that reiterated the same truthful statement: "I don't want to talk about it." Because honestly, she didn't.

Delivering the same scripted response, Neville, Ginny, and Dean alike groaned in annoyance. Only Luna, the one who asked the question in the first place, rubbed her shoulder and gave her a reassuring smile. It was uncanny how well that girl could read people.

Seeing that it was time for her nightly patrol, she excused herself with a forced smile and walked through the portrait.

They were good friends, truly. Ginny was rambunctious and humorous, Neville had a heart of gold, Dean was the co-voice of reason in their group, and Luna was - well, Luna was Luna. Prior to befriending her, Hermione always thought her to be too whimsical, with her head 'stuck in the clouds,' as they say. When Hermione was at her lowest point, with her best-friend openly antagonizing her, Luna was simply there. She always had a way of understanding others, and it was utterly refreshing unloading her volatile emotions onto Luna's calm, receptive persona.

They were all lovely. But it just wasn't the same. She didn't go on nightly walks with any of them, with a comfortable silence that was only obtained through a strong-enough companionship. She didn't talk about the most seemingly mundane subject matters for hours on end and still feel a pull to converse more. When she was upset, she didn't receive a back massage on her bed, nor was she held at night with the laughable excuse that 'she was warm.' Whenever she left for break, she didn't have a gaping hole in her heart, that could only be patched once she saw her best friend once more.

Because that's what they were. They were best friends. Inseparable. Hip-to-hip. The 'golden duo'.

Eyes beginning to become misty, Hermione wiped them furiously before tears could accumulate, and took a stabilizing breath.

What was wrong with her? She hasn't had these sort of emotional strings pulled since the fourth year. Clenching her fists, she took another deep breath and hardened her resolve. She would not think about Harry for the rest of the night. There were hallways to be checked! Kids to be potentially punished! There wer-

Right in front of her, looking back and forth between the corridor, was the girl she spotted during Harry's lengthy peroration. She was biting her fingernails in concentration and was accompanied by three books lodged between her arm and her waist.

"Hey there!" Hermione said, waving her hand to beckon the girl to come towards her.

She gulped nervously, which Hermione thought was downright adorable, and walked towards her with a strangely familiar lop-sided smile.

The girl began stammering immediately. "I'm sorry - I just got lost coming from the library. I-I took the 'shortcut' but lost myself along the way," she said, eyes dashing between her own to gauge her reaction.

Hermione chuckled, which in turn prompted the girl to timidly grin. Hermione smiled encouragingly at the girl. "It's fine - lord knows I used to lose track of time in the library," Hermione said, frowning at the prospect of the already apparent consequences of Harry's speech with the young ones. "Besides, if a certain boy didn't give you this path towards the tower, then you would be fine."

The girl giggled at Hermione's tone of voice regarding Harry. Eyes glimmering in mirth, she spoke through giggles, "Yeah, that guy is a bit of an oaf."

Hermione began to laugh whole-heartedly. "You have no idea-" she paused, "say, what's your name?"

The girl's eyes were shining in amusement, when she replied in a matter-of-fact voice, "I'm Rayla, Hermione."

Hermione stopped walking and was frozen in a perpetual state of shock. Of course. That's why she was familiar! It was nearly four years since she last saw her when Hermione visited Harry over the summer.

Despite herself, Hermione immediately hugged the girl, letting out a shaky laugh of disbelief. "I'm such an idiot," she murmured, shaking her head in the girl's locks. After letting her go, she was immediately met with two dazzling green orbs. Those damn eyes. "You've grown up so much Rayla! How's it been?"

Rayla was still looking at her with what seemed to be barely concealed amusement. "I've been fantastic! I never got rid of the copy of Hogwarts: A History that you gave to me over that summer," she said, eagerly holding up the weathered down book Hermione was enamored with during her first year.

By the time they arrived at the portrait, they had discussed her future curriculum, as well as the workload throughout each year. Did I really have this much of an impression on her? Hermione wondered to herself.

After explaining to Rayla that her shift wasn't over, the girl bit her lip nervously and stammered almost incoherently. "Why do you and my brother hate each other now? You two were the best of friends, and I know that we 'grow up' but you two seemed so inseparable and now you're-"

Hermione cut her off with another hug. "Listen, Rayla," she sighed, not knowing what to tell the young, impressionable mini-potter, "sometimes things naturally fall apart - and we don't hate each other."

Rayla scoffed while shaking her head in amusement. "From what I've heard from just today, and the snippets that Harry lets out at home, there is no way that what you have now is 'natural'."

Hermione noticed her head movement and was immediately reminded of all the times he used to perform the same head shake when he was exasperated. Grinning despite herself at the memories, she chuckled at Rayla's intuition. "Perhaps you ought to ask your brother these questions," she softly said, ruffling her brown mane of hair.

Smiling once more, Rayla nodded and walked into the common room.

Harry was working diligently on his transfiguration essay, alone in the common room. He had opted to skip patrol in an attempt to get an edge on Hermione. Ron called him 'incorrigible' and 'petty,' but he could care less. He imagined the look on her face when Hermione would be in the stands, when he would be valedictorian, giving the speech to the graduating class - and immediately whatever 'pettiness' was surely worth the result. Also, being first in the class would shut her up for good. Hermione, being herself, was first in the class, with just three more outstandings than him - which ironically was because of her. Harry grimaced at the thought of his third year, and what caused his academics to suffer.

His 'petty' musings were interrupted when, lo-and-behold, his sister Rayla walked through the portrait with an enormous grin on her face. Upon seeing him, Rayla's grin somehow expanded.

Harry, bemused at the fact that his little sister was out late on her first night, walked over to the couch facing the fire and motioned for her to sit with him.

Rayla immediately leaned into her brother's shoulder and began to giggle upon seeing his puzzled countenance. "I saw your friend on my way back," she stated, muffling her occasional giggle into his arm.

Harry with an eyebrow raised at his sister's antics, groaned in an exaggerated matter. "Well… I guess I'm down one after you got your hands on 'em," he replied with feigned graveness.

Rayla gasped in mocked indignation, pinching stomach in retaliation, which caused him to ruffle her hair. Pausing, she looked at Harry curiously. "She did the exact same thing with my hair y'know."

Harry looked at her, slightly taken back. He had a few girl-friends, but not many that were familiar with his sister. "Was it Ginny?" he asked, then dismissing that idea because he never saw her leave the common room.

Rayla only grinned slyly in reply. Harry stiffened. No. Was it? She did leave the room and hasn't returned yet. Harry, seeing Rayla's only increasing grin, groaned, and faced the heavens. Of course.

"Hermione."

"Yep."

Harry promptly faced memories he attempted to bury a long time ago. Memories of a 13-year-old Hermione during their second-year summer break, teaching Rayla how to ride a bike flooded his mind.

"Now Rayla, it's important that you aren't afraid. If you become frightened, your control on the bike will certainly cause you to fall," Hermione stated, speaking as if teaching a kid how to ride a bike was an oral exam.

Harry shook his head in exasperation. "Rayla, don't listen to this robot. Don't be afraid of falling - it won't hurt because we're on grass!"

Rayla immediately hopped off the bike upon hearing Harry's admission that she would fall.

Hermione huffed, crossing her arms. "Honestly Harry, you just scared her! At least my instruction would lead to an attempt," she said, whispering encouraging remarks to get Rayla back on the bike.

Harry, bemused at Hermione's teaching, watched the interaction with a fondness he was unfamiliar with.

"Harry, are you alright?" Rayla asked, concerned at her brother's shallow breaths.

"I'm fine, 'Ayla. Let's get you to bed, it's awfully late."

Rayla reluctantly followed Harry upstairs, but before entering her dormitory, she gave Harry a hug. Pulling away, she looked into his smiling, but undeniably torn face, and bit her lip in anticipation. "Why do you and Hermione hate each other?"

Harry shook his head tiredly. "Maybe you can ask Hermione when you see her next," he softly answered, with an unmistakably forlorn look in his eyes.

Sighing, Rayla entered her dormitory.

Unbeknownst to the two Potters, Hermione at the entrance of the common room, with her wand drawn, was listening to their conversation with a pained expression.

A/N: So, that was the first chapter! I'll be writing ahead, and I'm going to be aiming for 3-5k chapters each.

This chapter had minimal interaction between our two favorite characters. That won't be the case for future chapters. There's gonna be a lot of banter, arguing, and overall tension between Harry and Hermione. Of course, it will get resolved - along with the reveal of what drove them apart.

If someone guesses in the review section, I'll you a dollar.