Disclaimer: Any recognizable situations and characters are the property of J.K. Rowling, etc., and were used without permission. I'm not claiming them as my own nor am I using them for profit. It's Rowling's universe; I just play in it.

A/N: So begins the "Great Experiment." I'm not quite sure how this fic will turn out, but I'm hoping for the best. I've been having a lot of free time to write, so I expect to be able to update at a fairly constant rate. If you have any suggestions on how this story should go, feel free to tell me. I'd love to hear it. At any rate, I hope you enjoy.

- The Sanctity of Blood, 1488

• • • • • • • •

"She looks nothing like a Black."

Those were my father's first words the moment he laid eyes on me shortly after I was born. My father, not the most trusting of men, quickly performed a Paternum Charm to confirm my parentage. It was no small wonder, his misgivings. My hair was a light blonde, my eyes a pale blue, and my cheeks a rosy pink—a far cry from the raven hair, jet black eyes, and sallow skin of my two elder sisters… as well as every other Black in the past century and a half.

I might not have worn the Black ancestry on my face, but there was no doubt that I carried it in my blood. The tip of his wand burned bright green, confirming that he indeed sired me. Of course he did. My mother may not have been the cleverest witch, but she was far from stupid. She would never have carried a child that wasn't Cygnus Black's to term.

Though growing up I would draw suspicious stares as I stood with my sisters, I did not resent my appearance. I was the beauty of the family precisely because I looked nothing like them. Not to say that my sisters were ugly; far from it, really. The Blacks were known of their dark, stunning good looks. But my beauty was different—delicate and shining—and thus lauded by outsiders.

"You're fortunate," Lucius had always said, "that you don't look a thing like your sisters. Why else do you think I chose you?"

That, of course, was a lie.

I wasn't the first choice when they were picking Lucius Malfoy's bride. Or even the second. Bellatrix—brilliant, brave Bella—was the eldest and was thus given the honor of being the bride of the Malfoy heir. But even at a young age, she was headstrong and difficult, and she flat out refused to be married off in such a demeaning way, especially to a boy three years younger than herself. Bella claimed that when she married, it would be on her own terms; and in those days the would-be bride had veto power in all arranged marriages, much to the disgust of my aunt Walburga.

Naturally, Andromeda was the second choice. Andy was the obedient one, the perfect daughter that would one day be the perfect Malfoy bride and wife. She, like Bella, inherited the striking family features of midnight black hair and pale skin; but that was where their similarities ended. Bella's face was sharp and pointed, where as Andy's was soft and curved. Bella was loud and forceful; Andy was soft-spoken and yielding.

This is reason she agreed to marry a boy she didn't know at six-years-old. That is, she was six when our parents signed the contract that bound her to be wedded into the Malfoys. It wasn't an uncommon practice—childhood betrothals—especially amongst pureblood families. Such alliances ensured the continuation and purity of the line.

Even though I was five, I still remember the day of Andy's betrothal as clearly as if it had been yesterday. That was the day that I first met Lucius Malfoy.

Despite his only being a little boy of six years old, he looked so serious. His long white blond hair was tied back, and his face still held the roundness of youth. There were rumors floating around back in those days that he was part Veela. Though he was beautiful enough to be considered one, I knew that Malfoys wouldn't tolerate that sort of taint in their bloodline.

Growing up, I always thought of Lucius Malfoy, first and foremost, as being Andy's fiancé and therefore ours by right. In my child's mind, no one could or should be closer to the Malfoy heir than the Black sisters. I would get into nasty fights—secretly, of course, as proper pure-blood ladies never fight—defending our claim, hexing any girl whom would dare maintain that Lucius was hers simply because of a fleeting dalliance.

I needn't have bothered, looking back. Lucius Malfoy treated us with civility, but not much else. He tolerated my company only because I was the youngest Black sister and he had a mutual—if grudging—respect for Bellatrix.

Andromeda, I noted, was ignored almost pointedly, as though he was burdened enough by the thought of sharing the rest of his life with her, and he didn't need her to be doting on him throughout school either. This pained me because I adored Andromeda, and a slight on her was a slight on us all. Less altruistically—childishly—I knew that I would be completely devastated if he ever chose to ignore me.

Lucius was handsome, clever, and so popular that he made everyone around him more popular through sheer proximity. Being around him was a heady rush. When I was younger, I loved his attention. It was like the warmth of the sun in the Slytherin dungeon, and everyone sought after it. That is, everyone but Bella and Andy. Bella, because she was much too old to be charmed by Lucius, but Andy….

In reality, Andromeda didn't care a whit about Lucius Malfoy mostly because she didn't care a whit about anything our family stood for. She cared nothing for the sanctity of blood, or the Principle, by which our family lived and breathed. Centuries of glorious pureblood ran through her veins, and she wasted it all on a Muggle-born nobody named Ted Tonks. My perfect, wonderful sister was a blood traitor.

After eloping with that Mudblood, breaking a ten-year-long betrothal and magical contract, and costing my father a thousand galleons because of it, Andromeda was promptly disowned and blasted from the family tree. Mother had our house elves scour and destroy her presence from every family picture, portrait, and record. For all accounts, the Blacks never had a daughter named Andromeda.

I'm not heartless. I wanted to mourn my sister, as though she had died and was lost to us, but I was forbidden. She wasn't a Black anymore—it was as simple as that. Andromeda wasn't just disowned. No, she ceased to exist, and one cannot mourn the death of someone who never existed to begin with.

This is where I come in. Despite two failed attempts at uniting with our house, the Malfoys still wanted a Black bride for their son. They agreed to settle for third best, but really they had no choice. The family fortune may not have been as great as theirs, but Black blood was pure enough to rival their own, and our unyielding devotion to the Principle was indisputable.

Still, they took their own precautions. The penalty for breaking my betrothal would be doubled. The date for the wedding was set on the day after my graduation from Hogwarts, so my chance for escape would be minimal. They would have demanded that I married that summer, but my parents insisted that I finish my schooling first. The Malfoys relented, seeing as their son was still in school as well.

And finally, the Malfoys demanded our betrothal be bound by the Unbreakable Vow. My parents agreed. Their highest ambition was for all their daughters to be respectably married, and since Andromeda had failed them miserably at that, my marriage would have to suffice.

My betrothal ceremony to Lucius Malfoy occurred late in the summer before my sixth year at Hogwarts. Andromeda had run away earlier that same summer, and the Malfoys weren't wasting any more time to secure their son's future wife. It would be a quiet and hurried ceremony squeezed in between the last of the summer balls and the train-ride from King's Cross, with only our immediate family present.

There had been a cry of protest at the use of the Vow to seal the betrothal. Many considered this extra precaution overkill. However, any objections to the use of the Vow, or the possible dire consequences thereof, fell on deaf ears. It didn't matter to me whether the oath I swore to Lucius would be unbreakable or not. This was about family honor. Andromeda had shamed us, and it fell to me to prove the worthiness of our line.

Lucius Malfoy was going to marry a Black whether he wanted to or not.