A/N: This is my first publicly shared FanFiction. (To read more about my first attempts at writing FanFics, see my bio...)
Let me lay it all out. I have a very extravagant plot line laid out, to some extent. I have done the math and come up with a few figures. My current story line has a plot involving: 1 Alternate Universe, 3 Generations, at least 12 Original Characters, and a total of about 25 Books. Go ahead, call me crazy.

I Know I'll Be In Slytherin,

~M.J.W.

I Solemnly Swear

Chapter One – A Black Beginning

There was a street in London lined on one side by tall, expensive-looking buildings. If you walked along the opposite side of the street, you would come across a small, grassy area that could be called a park. Look across the street, and you would find yourself staring up at Number 11, Grimauld Place. To the left of this was Number 10; to the right, however, was Number 13. It would appear, to the ordinary person, that someone had - perhaps - made a mistake when they numbered the buildings. Or perhaps Number 12, Grimauld Place had never existed in the first place.

The fact was that Number 12, Grimauld Place, was exactly where it was supposed to be. It was simply not possible to see the building. You see, the house in question was, in fact, inhabited by a wealthy, pureblood family of wizards known as the Blacks. And, at the moment, eleven-year-old Sirius Orion Black was dreaming of the next day, when he would be starting his academic career at Hogwarts School of Witchcraft and Wizardry.

~ S ~ O ~ B ~

A loud crack rent the air, rudely and unceremoniously interrupting Sirius' sleep. He sat bolt-upright, got caught in a tangle of sheets, and toppled with a shout onto the floor. He lifted his head and glared at the house-elf standing in the middle of his room. Kreacher smirked at him.

"The Mistress wishes for you to be washed, dressed, and down for breakfast in half an hour," he said, his eyes glinting. "You will be leaving for King's Cross Station in one hour's time. That is all." Before Sirius could leap to his feet and wring the damned house-elf's neck, Kreacher snapped his fingers and vanished with another loud crack. Grumbling, Sirius detangled himself from the sheets and stood, stretching.

Sirius' room was large with dark grey carpeting and deep, forest-green walls, all four of which had intricate silver designs imbedded in the wood. Heavy, dark green curtains hung across the window on a silver bar, and a dark oak set of drawers sat against one wall, above which hung a large, silver-framed mirror. On the wall across from the solid oak door that led to the landing was a smaller door that opened into a large closet. The king-sized bed was also made of oak, the four feet carved to look like coiled serpents and the sheets midnight-black silk, to match the black comforter.

Sirius kicked the blankets away from him, leaving them for Kreacher to deal with. He despised the filthy thing, but his mother had forbidden him from giving the elf clothes. Setting him free could allow some of the Black family secrets to escape with him, risking the darkening of their family name. When Sirius had proposed the idea that they could just kill him and stick his head on a shelf, his parents had shared a slightly proud and hopeful look that he could be changing for the better, but his younger brother Regulus had cried in protest and horror. Kreacher and Regulus could almost be considered friends; the elf favored Reg over any other family member, and Reg was always overly nice to him because of it.

Sirius scowled at the thought and set about getting dressed. He pulled out his favorite Muggle tee-shirt with a sly smile. It was plain black, with a single word written across the front in white letters: "Mischievous". He knew his mother would never let him wear it, so he decided he'd have to put it on under his dress clothes. He stripped off his pajamas and pulled on the shirt and a pair of black denim pants. Grinning at his reflection in the mirror, he was glad he had snuck out to buy the Muggle attire over the summer. He hadn't wanted to meet his classmates wearing a Muggle suit; it was unnatural for an eleven-year-old to wear that sort of thing, and he didn't want to stick out for something like that.

With a sigh, Sirius reached for the suit in question and buttoned the dress shirt over his tee-shirt. Getting the suit pants over his denims was more difficult, but he finally managed it without it looking too suspicious. He heard footsteps on the stairs and quietly threw on the suit jacket, running a hand through his hair to straighten it.

"Sirius!" came Regulus' whining voice from outside his room. "I can't tie my tie. Can you help me? Please?"

Sirius sighed and opened the door.

"Come here," he said, stepping aside to let his brother in. Regulus gave him a grateful, relieved look.

"Look, it's not that hard," Sirius said, undoing the knots Reg had managed to tangle his tie into. "The wide end has to be on the right. You cross the right over the left, wrap it around the back, bring it upwards, pull it down through the loop and to the right, wrap it across the front to the left, then wrap behind and up through the loop, the tuck down into the loop on the front. See?"

Regulus was staring down at his finished tie with a baffled expression. Sirius sighed again and tightened the tie, straightening his brother's shirt collar.

"Thanks so much!" Reg said, beaming up at Sirius, who rolled his eyes with a slight smile.

"No problem," he said, patting his younger brother on the shoulder. "Hopefully you won't need help while I'm at school. It'd be hard to help you through owl post."

Regulus giggled.

"Promise me you'll owl me when you get there?" he asked.

"I promise."

"Do you swear?"

"I swear on my wand." Sirius raised his right hand with a smirk and Reg smiled, satisfied.

"Thanks," he said. "And thanks for helping me with my tie. I don't know how you do it." The younger boy beamed up at his older brother and hurried from the room, his footsteps scampering back up the stairs to his bedroom.

Sirius chuckled. He really did care about Regulus, even though he could be annoying sometimes. He couldn't wait for Reg to join him in Slytherin which, of course, was where Sirius was going to end up, he was certain of it. His entire family had been in Slytherin, so why would he be any different?

After one last look in the mirror, Sirius double-checked that he had packed everything in his trunk and started downstairs for breakfast. Ignoring the house-elf heads that lined the walls, he took caution to ensure that his Muggle clothes were well-hidden. If his mother or father found out – well, to put it bluntly, Walburga and Orion wouldn't think kindly of having that in their house.

Sirius took his usual seat at the table, on his father's right-hand side. Orion sat at the head of the table as the head of the Black family, and his wife sat across from him. Mrs. Black gave her son a piercing, scrutinizing stare; Sirius felt his hands shaking but, but kept a confident expression on his face. It was just the routine inspection, to make sure he looked perfectly presentable before going out in public.

"Did you wash?" his mother asked sternly. His heart plummeted. After a moment, he swallowed.

"N-No, ma'am," he said, not daring to break eye contact. Mrs. Black's eyes narrowed.

"Did I not ask that you wash before breakfast?" she asked, her voice cold and unforgiving.

"Y-Yes, ma'am," Sirius said quietly.

"And why did you not do as I asked?"

"I f-forgot – "

"You forgot?" she said icily. "You use that excuse for everything you do. And where do you think you're going?" Sirius had made to stand up.

"I was going to do as you asked," he said.

"Sit down," Mrs. Black hissed at him. "Don't bother now, you'll have to wait until we've finished eating." Sirius sat and nodded stiffly. He broke eye contact and his gaze landed on Regulus, who was frozen in the doorway, looking uneasy. Sirius gave his brother a small smile and the younger boy walked cautiously to his seat across from his older brother.

Reg stiffened as his mother's stare turned to him – though, Sirius noted, the look she gave him was much less cold and piercing; for her, it could almost be considered kind. Sirius had to refrain from scowling at the unfairness of it.

After giving her younger son a satisfied nod, Mrs. Black summoned Kreacher to serve breakfast.

~ S ~ O ~ B ~

Sirius soon found himself climbing into, what he was told was called, a limousine. He was fascinated by the sleek, black, Muggle vehicle. Of course, he was unsurprised to find the interior had been magically enlarged – and unhappy to see that his cousins were already in the...what was the word...'car'? Yes, that sounded right. For the third time in an hour, Sirius fought the urge to scowl, the second time having been when Kreacher "accidentally" dropped Sirius' trunk on the owner's foot in the front hall.

He decided on a seat across from Andromeda, who was leaning against the window and blatantly ignoring her sisters. Andromeda had been sorted into Ravenclaw, to the slight disappointment of her parents, but it was the next-best house to Slytherin so they merely passed it off as being due to their daughter's higher intelligence. Her sister Bellatrix, who had been in her fourth year at the time, had teased her about it until she herself graduated a few years later. Bella had left Hogwarts three years ago, but was coming along to see Sirius off...and, more likely than not, to ridicule her young cousin.

"Hello, Siri," Bellatrix simpered with a false sweetness. Sirius, again, fought the urge to scowl; he despised that nickname. "Ready for Hogwarts?"

"Hello, Bellatrix," Sirius said emotionlessly. "And yeah, I am."

"You'd better be in Slytherin." Narcissa said with a sly smile from beside her sister. "I highly doubt you'd be lucky enough to end up in Ravenclaw on the off-chance you don't make it, and as for Hufflepuff and Gryffindor – well, let's just say that either house would result in your disownment." She paused and tapped her chin thoughfully. "Or...I suppose, you could get worse than just disownment..."

Sirius rolled his eyes at her.

"Then I guess I've got nothing to worry about," he said.

"Quite right," came a voice from somewhere to his right. He looked past Regulus and his mother to see his father giving him a 'You had better now screw this up' sort of glare. Sirius swallowed and quickly turned back to the window, where he saw other Muggle vehicles speeding past. He stared curiously as some sort of metal contraption on the sidewalk. It was made of metal rods and had two large rubber wheels, one in the front and one in the back. A Muggle sat perched on a small seat attached to it and was holding tightly to a pair of handles on the front.

"It's called a bicycle."

Sirius looked around and saw Andromeda smiling at him. He grinned back.

"Thanks," he said. Then, after a pause, "What's a bicycle?" Andromeda laughed.

"It's like the Muggle equivalent of a broomstick, except instead of flying, it travels on the ground." Sirius stared at her.

"What's the point of that?" he asked, as if it was the most ridiculous thing in the world. "It doesn't fly?"

"No," Andromeda smirked. "It's not supposed to."

"It should," Sirius mumbled. "Bloody boring otherwise."

"Whatever you say," sighed Andromeda with a lopsided smile.

"You shouldn't say that!" Regulus whispered into Sirius' ear. "Mum and Dad wouldn't like you saying that!"

"What, 'Bloody boring'?" Sirius asked. Reg's eyes widened to the size of saucers. Andromeda laughed.

"Sirius!" Reg hissed, and Sirius smirked at him.

"Baby," he muttered, so his parents wouldn't hear. Andromeda rolled her eyes.

"Sirius, be nice," she said, smiling at the younger Black brother.

"Come off it!" Sirius protested. "He is, Andromeda, and you know it!" Andromeda shook her head as Regulus pouted.

"Whether he is or not, you still shouldn't call him names," she said softly. "You're his big brother. You should be standing up for him, not knocking him down."

Sirius winced. He knew she was right, but, as she said, they were brothers. Brothers always fought and bickered once in a while, didn't they? Despite this thought, Sirius let out a sigh and said, turning to Regulus,

"I'm sorry. I shouldn't have said that." Andromeda smiled in satisfaction and Regulus grinned.

"It's alright," Reg said. "Besides, I know you didn't really mean it..."

"Oh!" Sirius said suddenly, turning back to his cousin. "How good are the Quidditch teams at Hogwarts?"

"Thinking of joining, are you?" Narcissa interrupted, giving him an amused look.

"What's it to you?" he asked crossly.

"Oh, I'm sure she just wants to know so she can mark the date on her calender...that way she can come to your trials and watch you make a complete fool of yourself," Bellatrix said with a smirk. Narcissa cackled with laughter.

"Hush, Bella," Cygnus Black said coolly. Cygnus was Sirius' uncle on his Mother's side, and Bellatrix's father. "Where are your manners?" His wife, Druella, gave Bellatrix a soft but pointed look.

"Yes, father," Bellatrix said obediently, though with a slight smirk as Narcissa clamped a hand over her mouth to stop laughing.

"Why don't we maintain silence until we reach the station?" Walburga asked icily. "I do apologize, but all of your bickering is giving me a migraine."

"Yes, Aunt Walburga," Bellatrix and Narcissa chorused immediately.

The remainder of the car ride was spent in near silence, interrupted only by the driver occasionally announcing the time left until they reached their destination.

~ S ~ O ~ B ~

The train station was quite intriguing, in Sirius' opinion, though he didn't dare voice this aloud as he feared what his mother would think of such a comment. Hiding his fascination, he pushed his trolley after the rest of the Black family, all of whom were ignoring the Muggles completely – though, Sirius was nearly certain he spotter a faint glimmer of interest on Andy's face as they passed a girl in her teens wearing bell-bottom jeans, a loose tie-dye shirt, and a matching headband in her waist-length blond hair.

'Well,' thought Sirius, 'it sure looks more comfortable than that dress Andy's wearing.'

This was quite true, as the dress in question was a black, formal, floor-length gown with a rather tightly-fitting bodice and sleeves that were a little constricting, in Andromeda's opinion. She planned on transfiguring the horrid attire into something more practical the moment she reached her compartment.

As they neared the barrier between Platforms 9 and 10, Sirius got the best idea for a way to prank Bellatrix as a way of getting back at her. Knowing Bella, her reaction would be priceless.

End of Chapter One

A/N: Thank you so much for reading my first FanFiction chapter posted in the history of forever! Please leave a response! Critiques wanted...PLEASE tell me any and all opinions, good and bad! I "Siriusly" want to know what you think! (Okay, that was just bad...I'll be sirius from now on.) Hahaha...anyways! Read my profile for extra information!

~M.J.W.