(Minor formatting correction & Author Notes expanded slightly, 27th September 2014)

Disclaimer: I am not J.K. Rowling. I do not own Harry Potter.

Note: The following one-shot where Bellatrix earlier developed a slightly different primary obsession from that which she apparently had by the time that she is seen in canon. This story is a brief look at the development of that obsession, and is a one-shot. This story is rated 'T'.

"I want a Prince." Bellatrix, a nine year-old girl, folded her arms and huffed. "Not any 'Lestrange'. 'Lestrange' sounds stupid and foreign."

Bellatrix Black's father, Cygnus, sighed.

"Is it a Prince?" Bellatrix peered at the picture of the baby.

"It's the son of one." Cygnus sighed. "Of a witch who married… a muggle. He's called Severus Snape."

"Muggle names don't count." Bellatrix said scornfully. "That makes him a Prince. And Severus is the name of a Roman emperor, right?"

"He's a half-blood and he's nine years younger than you, Bella." Cygnus said.

"Is he the only Prince around?" Cygnus' daughter demanded.

"Yes." said Cygnus. "The only one on the marriage market, at any rate."

"Fine. I'll wait." Bellatrix said. She narrowed her eyes. "If his mother married a muggle then she should be desperate for any witch of decent family for her son, right, and she won't expect a big dowry or anything either, will she?"

The negotiations with Eileen Snape, née Prince, proved tricky, not least because of the literal muggle in the room.

Bellatrix supposed that at least the muggle looked big and strong, even if rather stupid. He didn't look happy about all the talk going on about matters much beyond his station and ability to comprehend, though he did at least grasp that Cygnus Black was a member of a powerful and influential family, and that for some reason Cygnus seemed to want to drop by to visit occasionally.

Bellatrix knew her father just thought that this was 'a phase' and that she would get tired of it and find something else to interest her; that just made Bellatrix more stubbornly determined to see this through.

Bellatrix refused to give up on her 'Prince' project, with the passage of the years, even though said passage of time only served to increase her general dislike of muggles in general. Her pride refused to let her 'back down' from her expressed objective of marrying a Prince, and in the end, her father caved in and drew up 'necessary documents against the eventuality' of Bellatrix trying to her force her designs on Severus Snape through to the end.

She became fascinated, in the meantime, with the highly charismatic and mysterious wizard who called himself 'Lord Voldemort', and who, as her own school-days drew towards a close, she became involved on the periphery of the organization of. A lot of what he had to say about muggles, in particular, matched up with her own perceptions of what happened in the Snape household. They were uncouth and uncultured muscle, completely unsuited for anything except menial tasks and amusement. Bellatrix suspected if Eileen Prince's father hadn't been quite so hasty to disown Eileen for her marriage to the Snape muggle, she would have taken her son and returned to her true home, years ago.

Although she didn't think much of actual muggles, Bellatrix considered muggle-borns cute but potentially dangerous pets. Apparently Severus had one in his neighbourhood, whom he saw. Bellatrix would rather that he had no kind of associations with anything so lowly born at all, but cut off as he and his mother were from magical society of any kind (except the occasional visits by Bellatrix and her father), a muggle-born was probably the closest that he could get to conversation with an equal.

Severus finally arrived at Hogwarts, a couple of years after Bellatrix had left. Fortunately for Bellatrix, one of her younger sisters, Narcissa, had designs on Lucius Malfoy, who had just become a prefect in Slytherin this year; Bellatrix consequently got Narcissa to task Lucius with keeping an eye on Severus, to see how he fared.

As it happened, since Severus ended up sorted into Slytherin, Lucius' job was much easier than it might otherwise have been.

The… muggle-born… who lived in Severus' neighbourhood, with the passage of the years, was beginning to annoy Bellatrix. She went to her father for advice.

He asked for details, and when she told him, he laughed.

"Just. Wait." Cygnus said.

Cygnus seemed to think that there was no way that the association of Severus with the Lily girl would survive the time at Hogwarts with the gulf between Gryffindor and Slytherin between them.

So Bellatrix waited. It was pretty much time she'd be waiting anyway. And she resolutely sat on her hands and did nothing as far as Severus' acquaintance with the redhead Gryffindor was concerned.

Her cousin, the blood-traitor-in-the-making, Sirius, and his gang of three cronies were doing their best to provoke a sense of contempt for all things Gryffindor in Severus anyway, far more effective than anything Bellatrix could do, she reckoned. And Severus knew that Bellatrix was there, and waiting for him, for when the inevitable happened – unless there were any other girls that happened to catch his eye, but surely any Slytherins would have the sense not to try anything with the knowledge that there was a likely 'arrangement' with the Black family awaiting Severus?

And in the meantime it was interesting for Bellatrix to note that by all accounts Severus was apparently quite good at potions and highly inventive when it came to not just using but even creating spells.

Bellatrix was unexpectedly afforded an interview by Lord Voldemort himself. He'd noticed her involvement in his organization, he said, and he was interested in inviting a daughter of a noble family such as herself to take the mark and join his inner circle.

Bellatrix hesitated long and thought hard. She explained that she had a long-term plan currently in operation to which she was committed to salvage something out of the wreckage of the Prince family. She explained what she knew of Severus. Voldemort listened attentively. At length he graciously accepted her declination, on condition that she rethink her position should her interests in Severus Snape prove less than fruitful.

Finally, towards the end of Severus' fifth year, the bust-up which Bellatrix had been waiting for came. Sirius Black and his gang provoked Severus to at last come out and call Lily a 'mudblood'. It was probably his muggle father's influence in his life which caused Severus to actually use the word. A true-bred aristocrat wouldn't actually deign to say anything like that in a mere fit of temper. The Lily girl, full of self-righteousness, and blind to the imperfections of her fellow Gryffindors, naturally haughtily declined Severus' attempt to apologise.

Bellatrix was there for him once school broke up.

Arrangements were made for their union to occur during the Easter of the following year, in what would be the first school holiday following his turning seventeen and counting as 'being of age' in wizarding Britain.

Author Notes:

As far as I know, as of the time of the posting of this story, dowries are not mentioned in Harry Potter canon, but it seemed to me the sort of thing that some old pure-blood families might engage in. Obviously as far as this story goes, Cygnus Black is a father in such a family. I may take a different direction on this count in stories I write set in other universes though.

Bellatrix assumes that her cousin Sirius is the leader of the Marauders simply on the basis that he's a Black, so obviously, even if he's a blood-traitor-in-the-making he's in charge.

Bellatrix still supports Lord Voldemort and the Death Eaters in this universe. She's just slightly more obsessed with something else than them. Voldemort figures she's good to have even on the fringes of his organization, and especially if she brings Severus with her.

This story is a one-shot. I have a few notes for what might have happened in the next couple of years, which were basically that Bellatrix did marry Severus, and started a family. Severus became more of a political figure than canon, being married to a daughter of house Black, and involved on the fringes of the Death Eaters. Then, in 1981, as the war had been going against the Death Eaters by then for several years, Voldemort arranged for Severus to kill him in a highly public duel. Severus wasn't a known Death Eater, so the idea was that Severus could make a reputation defeating Voldemort the same way that Albus did, beating Gellert Grindelwald, and Severus could use that reputation to become Minister and start making appropriate changes. Voldemort, meanwhile, would have made arrangements beforehand to ensure that he was secretly resurrected by followers, so that he could then control events from the shadows as necessary. And that's where the notes run out. Probably no Trelawney prophecy, and Lily married James as per canon. No idea if James/Lily survived Voldemort's final killing spree before his epic duel with Severus.

Update, 27th September, 2014:

To respond to an early reviewer, Bellatrix in this story is sort-of-sane. She has a slightly healthier principle obsession than her canon counterpart, and not having been involved in the Death Eaters to quite the same extent as her canon counterpart makes for some further difference.

One further thing I had in my notes about how the story might go was that I tentatively had Bellatrix & Severus' first child sharing the birthday of one Tom Marvolo Riddle, which led to Lord Voldemort developing a fascination for said child...

To the guest reviewer, 'liz', who enquired after other stories, no, not on the 'archive of our own' website at the time of this update. I'd prefer to answer you by PM rather than stray further from the topic of this story, in these notes.