Matou Shinji and the Heirs of Slytherin

A Harry Potter / Fate Stay Night Story

Disclaimer: Though I wish it were otherwise, I do not own or in any way, shape or form hold a legal or moral claim to elements of either the Nasuverse, the Potterverse, or other works I may reference in the course of this story.

Summary: Trouble is brewing in the Wizarding World. In the wake of the Stone Incident, Albus Dumbledore has begun quietly preparing Britain to survive the coming war. The Stone Cutters, a new organization at Hogwarts for the most talented and distinguished of students, seek new blood to bolster its strength. The Boy-Who-Lived seeks his destiny as the Heir of Slytherin. And a boy from the east meets a specter of the past.

Chapter 1. One Master, One Apprentice

Matou Shinji sagged as he stared down at the slip of paper on the workbench in front of him, or rather, all that remained of it after channeling prana into it though his wand. He was sitting in a warded room, where Matsuo Hijiri, the maiden who guarded the great Tree and bounds of Mahoutokoro, had walked him through a series of exercises to test his skill at ofuda.

First, she had questioned him on his understanding of how onmyoudou and witchcraft were linked, mentioning that this particular style was fairly recent, as it had only begun to be practiced after World War II. Prior to that point, onmyoudou (which itself had once been a combination of other traditions and systems) had been the leading magical tradition in Japan, with Witchcraft existing as a separate, less popular tradition imported by some of the early Dutch merchants who had come to Japan for trade opportunities.

What few practitioners of Western magecraft existed in those days were refugees (like the Makiri) and secret Christians (like the Tohsaka), with neither Church nor Association able to establish much of a presence in the East, given that the bulk of their power had been committed to conflict in the West.

There had been some experimentation with blending witchcraft and onmyoudou, but nothing on a systematic level until the mid-19th century, when the Opening of Japan led to an immense amount of social upheaval. Among those changes had been the rise of Western Magecraft – as noted with the rise of the seven-generations old Aozaki family – and the official prohibition of onmyoudou as mere superstition, with even the once-proud Tsuchimikado family – descended from Abe no Seimei himself – forced to go underground.

Together with practitioners of witchcraft and other malcontents, they had moved their center of operations to Mahoutokoro, the city of magic created long, long ago during the Age of Gods. Given the nature of the city as a slice of the past, it had served as a refuge for youkai, oni, and onmyouji who did not want to deal with the rest of the world, and now served nicely as one for the rest of those the world rejected.

But this had complications of its own, as onmyouji had traditionally trained apprentices – something that was no longer possible now that they needed to hide their practice. So a collaboration was born, with the Mahoutokoro School of Magic being established, based in part on the model of Wizarding Education in the West, but with its own distinct flavor.

And why not?

As a sovereign "magical nation," they had the right to define the curriculum in the schools, to set their own laws with regards to interactions with non-humans, and whatever else they chose. It was well known that the International Confederation of Wizards was a largely powerless entity, after all, as the Magical Congress of the United States – or Liechtenstein, for that matter – regularly demonstrated.

Even Magical Britain, one of the most conservative in the world, where those who fraternized with Muggles at all were considered suspect – even outcasts, as well as being the very country from which Albus Dumbledore, Supreme Mugwump of the Confederation, had hailed, had defied the International Statute of Wizarding Secrecy without repercussion, with former Minister Bagnold defending their violation of international law by asserting the "inalienable right to party."

If anything, the Confederation had proven that it was a paper tiger, whose decrees and Statutes were usually unenforceable, given that most member nations were unwilling to embroil their witches and wizards in a conflict that ultimately would not benefit them or their regional sphere of influence (each of which roughly corresponded to the locations of the schools).

By far more important were bilateral and multilateral economic agreements within those spheres that were negotiated by various Departments for International Magical Cooperation, though even then, given the inward looking nature of each country and how little impact the work of this Department had on day-to-day living, being appointed to head this department was usually end of a politician's ambitions.

And given the precedent set by their leaders, most wizards spent their lives within these historic spheres of influence, exploring the possibilities they offered, save for a few eccentrics like Newt Scamander or Charlie Weasley. Even the famed Albus Dumbledore had never left Europe for any long period of time, with the exception of the occasional ICW meeting or conference in Brazil or so.

…truthfully, all of this was more than Matou Shinji had learned in History of Magic all year, which led him to wonder if Hogwarts truly was the finest school of witchcraft and wizardry in the world.

When he asked Hijiri how she knew all of this, she had noted that as the shrine maiden who was keeper of the City's boundaries and ways, tied into the network of portals and waypoints, as well as its defenses, it was her responsibility to know of the current state of affairs of the outside world.

That, and apparently, the History teacher at Mahoutokoro, Hyumurei Marito, apparently had an interest in the reality of international politics and international relations – unlike Hogwart's Cuthbert Binns, who didn't even know what year it was, or of any of the events of the 20th century. Though given how Japan had been occupied and forced to surrender during World War II, while Britain had not been overthrown by conquest since the time of William the Conqueror, as well as the fact that Japan was not a signatory to the International Statute of Secrecy, this was perhaps understandable.

The city was a strange thing in and of itself, and moving there had been something of a shock for Matou Shinji. Not in terms of being around wizarding magic and the like, as he'd gotten used to that at Hogwarts, but in terms of what he was expected to do on a day to day basis.

Waking up in the morning, Touko would send him on errands, with him retrieving food from the cafeteria, helping to fix things with Reparo (the Mending Charm), or clean up messes or make them waterproof with the Impervius Charm – all of which he rather thought unrelated to the actual work of apprenticeship, though the magus explained that she was testing his affinity.

As she put it, there were four general attributes that people had: Maker, Seeker, User, Destroyer.

Aozaki Touko described herself as a maker and a seeker, and she needed to see which his was before she could train him – if she chose to do so.

He'd seen some of the work she'd done.


Dolls, rather – dolls made so delicately, they seemed like frozen humans, caught the moment before they sprung into motion, yet it was clear that most of them were only human-shaped mannequins which would never would never move.

It was uncanny…particularly when her newest creation – seemingly a handsome teenage boy with pale skin, jet black hair, and eerie red eyes, stood up, and greeted Shinji politely, with Touko introducing him as Shinji's new Occlumency teacher.

She'd already taught him some of the basics of clearing his mind, after all, and said that the puppet, Tomas, would help him learn more.

…Shinji had been skeptical until this Tomas had used witchcraft. Wandless, non-verbal witchcraft, at that, which had made the Matou boy gape.

Her puppet could do witchcraft? How on…?

Shinji decided that it was better not to ask, and had simply agreed.

As such, his daily routine until now had been chores in the morning, Occlumency before lunch, work with Hijiri in the afternoon, and some socialization with Mahoutokoro students at dinner.

In his work with Hijiri, the shrine maiden had tested him on his current repertoire, watching as he demonstrated sealing, binding, warding, and more in both unpressured conditions, and in combat against her familiar, a five-tailed kitsune she called Kai-kun.

The woman, about Touko's height, with long, loose brown-black hair and eyes the color of dried blood, had not been especially impressed, but had found his work passable. And so, she had permitted him to test for elemental affinity, pacing a slip of paper before him from one of the great Tree's branches. Exposed to vast amounts of prana for hundreds of years, it would react to even the smallest hint of an affinity.

So Shinji had been told not to think of anything, to empty his mind and channel prana into the paper.

He had done so, with the result being a layer of thin, black mud which seemed to whisper in his mind, before it vanished, reality erasing the construct from existence.

"Fufu…so those are your affinities."


"Earth and Water. The former explains your facility with sealing and binding. The other…well, either you have a hidden talent for healing, or you will be very skilled at what is usually called the Dark Arts."

At her last words, Shinji shivered, thinking that even on his new path, he could not fully escape his past, given the Matou clan's traditional alignment with water – the element of healing, flow…and decay.

In his home at Spinner's End, Severus Snape was making preparations to attend the Wizarding Schools Potions Championship Committee meeting at Mahoutokoro. As Potions Master of Hogwarts, one of 11 wizarding schools in the wizarding world, he had a standing invitation to attend the planning committee's meetings, and while he would normally have declined, the Headmaster had asked him to take advantage of the invitation – and the Portkey – to take the Boy-Who-Lived to Japan.

Suffice it to say that this did not thrill him, as this meant a visit to the Dursley residence, and he was not looking forward to seeing Petunia Dursley (née Evans), again. He remembered her well enough, as a particularly unpleasant woman who had looked down on him and thought of him as a freak when they were both children. He remembered her as the woman who – in the wake of being rejected by Hogwarts – had rejected the magical world, growing to despise anything of that world – especially him (he distinctly remembered her calling him "that awful boy" more than once).

…but he also remembered her as Lily's sister – the woman who had arranged for Lily and James to be buried at Godric's Hollow, who had taken in their son Harry – a woman who had suffered because of what he had done.

If he only he had not told Voldemort the Prophecy, then maybe…

…but it was too late for regrets, eleven years too late.

Once again, the Potions Master had failed to protect Lily's son, with the young Potter having nearly died in his attempt to retrieve the Philosopher's Stone, losing a friend in the process. While he knew Albus suspected that the Dark Lord had gotten away with his prize, Severus was not so sure.

By now, there would have – should have – been some sign of the Dark Lord's revival if it really were the case. The Dark Mark becoming less faint, or some such, though he supposed the escape of Sirius Black from Azkaban might well qualify.

Sirius Black – the secret Servant of the Dark Lord – the Gryffindor who had seemed loyal to James Potter all through Hogwarts, only to betray them in the end. The man who not even Snape had suspected would be capable of such base treachery; the man who was ultimately responsible for Lily's death.

It was no secret that Snape had never trusted the man, that he hated Black and wanted to see the criminal's very soul ground into pieces and torn apart. So what if he'd been sent to Azkaban without trial? He'd been found laughing maniacally at the scene of a huge explosion that had presumably claimed the life of Peter Pettigrew along with 12 Muggles – that alone, the lack of remorse, the lack of grief, was enough have him shipped him off to prison.

And now, somehow, the man had escaped, with Snape fearing that he planned to come after Potter, given that Harry was the youngest ever recipient of the Order of Merlin, and had defied the Dark Lord twice now.

The fact that Black had been heard to mutter "He's at Hogwarts" before escaping was quite suggestive of that, and was why Dumbledore had ultimately agreed to let the young Potter leave the country, as Black would never look for him on the other side of the world.

Even if he did, in general it was difficult to gain permission to enter another wizarding nation without prior approval or clearance. International apparition was theoretically possible, but the extreme distance usually led to splinching, which was why it had been outlawed. Those taking one of the slower ways into and out of a country – magical or muggle - were recorded at the border, and the sheer morass of bureaucratic legalese involved in authorizing an international Portkey was prohibitive, though it was true that a powerful enough wizard – like Dumbledore or Voldemort – could just make one.

But in this case, Dumbledore wanted to leave no trace, so he had reached out to Tsuchimikado Masaaki, the Headmaster of the Mahoutokoro School of Magic for a favor, asking if Severus Snape could take a guest with him to the Committee meeting.

The request had been approved, and so the Potions Master would soon be on his way to Number 4 Privet Drive, Little Whinging, Surrey.

Not that Portkey travel didn't have its own issues, given the threat of serious injury, death if one's fingers happened to slip from the item in mid-transit, with one's constituent atoms scattered between origin and destination.

…this was one reason Portkeys had largely been discontinued for use in transporting students to Hogwarts. Prior to the creation of the Express, it had been the only way to get to the castle, but as it turned out, taking the train resulted in less injury, nausea, psychological distress, and other signs of Portkey sickness.

But enough – Severus Snape knew that he was thinking about things just to distract himself from the unpleasantness to come – seeing Petunia, having to meet Potter and take him to Japan, enduring remarks from some of his international colleagues about his failure to enter a student in the Championship as of yet.

…or rather, Hogwarts' failure to enter a student in over a hundred years, which rather cast doubts on both the schools' claim to excellence and the professor's claim to brilliance.

This he found particularly irritating, as he was sure he was the best Potions Master in Europe, at the very least – though he admitted that there were any number of magical plants and herbs that had not been studied for their uses in potions.

Witch's ganglion, for instance, a plant endemic to the Far East and whose properties were virtually unknown in the West.

Preacher's Porridge, for another, a plant rare enough that its properties had never been classified.

Even Niffler's Fancy, a rare plant which had almost been driven to extinction due to its leaves once having been used as currency by wizards, in which research was also lacking.

The schools in Africa, Japan, Russia, and Brazil tended to have their own concoctions and potions that the Western World was simply not privy to, which was why, out of all the other schools, they tended to field Champions in the competition regularly.

Hogwarts' international reputation was slipping, due to complacent – or utterly useless – faculty, and dunderheaded students who prioritized Quidditch over sensible things like studying and mastering their art, thinking that simply knowing the required material was enough, when that was only the very start of mastery.

It was, in many ways…grossly disappointing.

With arrival of the international students – one of which had more talent with potions than he had seen in years - Severus had thought that perhaps the School would have a Champion to field during the next competition, but then tragedy had struck.

The former Death Eater could only hope that what happened would motivate those who remained to take their studies seriously and to carry on her legacy.

After all, if properly motivated, one of the Weasley Twins might serve, as much as he disliked their antics. Failing that, he had hopes for either the Matou boy or the Dunbar girl, the latter of which had managed to improve the work of even the Longbottom boy (and truly, that was a miracle).

He would have to ensure that they learned something. Perhaps he'd even have to restart the Potions Club, or at least, take control of it away from Sprout, as he did not wish for such a club to be a place to catch up on homework.

A Potions Club, to him, should be a place to excel, to learn about new possibilities and delve beyond what other students dared.

Now, it might seem odd, as Severus didn't much like students, but there were three things the Potions Master disliked even more. The first was stupidity, which came as a surprise to none. The second was defeat. And the third – well, that should have been obvious from the past.

The third was ridicule. For to him, a man whose loyalties were in question, who no one really understood, image was everything.