'Humankind cannot gain anything without first giving something in return. To obtain, something of equal value must be lost.' - Alchemy's First Law of Equivalent Exchange.

"You think it will be real?" Hermione questioned anxiously, peering over Severus' shoulder as if she too could see down the microscope the wizard was using.

Severus just raised an eyebrow at her insistence, his dark eyes never leaving the microscopic examination before him. "Do you doubt my expertise, Granger?" he drawled, a smirk beginning to tug at the corner of his lips.

Hermione could only huff in response; her frustration evident. "It's not about doubting your expertise, Snape. It's about testing the boundaries of transfiguration. Gamp's First Law clearly states that you can't create food out of thin air. So, does transfiguration truly create 'real' objects, or is there some magical mimicry at play?"

Continuing to peer through the microscope, adjusting the lens with meticulous care, Severus took his time to reply. "You're referring to Gamp's culinary shortcomings," he stated, "Which, I might add, are hardly relevant to the current discussion. Transfiguration is a far more complex art than the simple conjuration of food." He finally glanced up to Hermione, that sardonic smirk still tugging at his lips. "Do you truly think the Ministry would waste the time assigning us this task if the answer were as simple as a yes or no?"

"Well, we wouldn't be here if they didn't think there was something to discover," Hermione conceded with a huff. "But I don't see why we need to delve into the very basics of Transfiguration and question whether a toothpick can truly become a living, breathing chicken."

"Ah, but that's precisely the point, isn't it?" Severus retorted, "Transfiguration, for all its complexities, is bound by certain laws, and one of those is Gamp's First Law."

The witch crossed her arms, her brows furrowing. "Gamp's First Law states that food cannot be conjured out of thin air. But we're not talking about conjuring here; we're talking about transfiguration. It's an entirely different branch of magic."

"You're missing the subtleties, as usual, Granger," Severus turned away from the microscope so he could face Hermione. "The question isn't about conjuring a chicken; it's about whether a transfigured object retains the essence of what it once was."

"The essence?"

"Indeed. Take this toothpick, for example," the wizard tapped the microscopic slide under the lens. "It may appear to be a mere sliver of wood, but it came from a tree, did it not - a living entity that expended energy and grew over countless years, perhaps even centuries."

Hermione's eyes widened as realisation dawned. "You're saying that even though the toothpick is small, it still carries the essence of the tree it came from."

"Exactly," Severus replied with a knowing smirk. "And if transfiguration truly transforms one substance into another, then the essence, the magical energy that once fuelled the growth of the tree, must persist within the toothpick. It follows that we could, in theory, transfigure a toothpick into a living creature."

His bushy-haired companion's mind whirred with thoughts and objections, but Hermione remained silent, absorbing Severus' explanation with a patience both had wished she'd possessed in school.

"Now," the wizard continued as he stood from his chair, "Imagine a skilled and powerful wizard channelling magical energy into the transfiguration process, infusing the toothpick with life. Theoretically, a chicken, or any living being, could emerge."

Sighing, Hermione tried to grapple with the implications of what her partner was proposing, but finding herself stubbornly unable to let go of her beliefs. "But that's... that's Alchemy! Transfiguration is about changing form, not creating life."

Severus could only chuckle at her expected response, a low and mirthless sound escaping his lips. "Ah, Miss Granger, you always were too rigid in your definitions. Magic is not confined to the neat little boxes you wish to place it in. Transfiguration, Alchemy - they are but different facets of the same magical spectrum."

"But how can you be so sure?" she questioned, torn between fascination and incredulity. "How can you know that the chicken, if transfigured from a toothpick, would truly be alive and not some magical imitation - like a golem?"

Severus' eyes glinted with something akin to amusement as he watched the bushy-haired witch try and wrap her head around what he was revealing. It was the times like this that made working within the Department of Mysteries worthwhile, knowing that he knew something that Know-It-All didn't, and it was something he revelled in.

"Because, my dear Unspeakable," he continued, pushing his chair back away from the desk. "I have dabbled in areas of magic you can scarcely imagine. I have witnessed the boundaries between all its branches blur, and I have come to understand the interconnectedness of it all." He suddenly stood, his white robes flowing around him in a familiar billowing fashion as he moved towards a cluttered shelf. After a moment, he produced a delicate silver vial that was etched with so many runes they made Hermione's head spin, and was filled with a dark, inky-like substance that the witch felt she should have recognised.

"What is that?" she asked instead, eyeing the vial warily. It wasn't that she didn't trust Severus, she did. But she knew that he still found a perverse amusement at getting a rise out of her, and if scaring her with something unexpected had to be done in order for him to succeed... well, Hermione had first hand experience at just how far he was willing to go to mess with her.

The day she'd walked in on Severus and Harry sharing tea whilst talking about the older wizard's time at Hogwarts had almost given Hermione a heart attack. Until, that was, of course Harry had turned his green eyes towards her and suddenly McGonagall was there yelling at her that she'd failed her NEWTs and had to give up her wand and magic.

She had not been able to look at Severus for a week after that without wanting to hex the damnable wizard into oblivion. And Harry! Poor Harry had almost lost his marbles after Hermione had explained to him why he'd almost been blasted back through the floo via one very pissed of otter Patronus after he'd called to check in on her that very same afternoon.

"This, my inquisitive colleague, is something of my own creation - a... blend, if you will, of alchemical and transfiguration principles." Severus' voice pulled Hermione from her memories as his tone changed, lowering as it took on a conspiratorial tone she'd once believed he's been unable to possess. "Now, watch closely."

With a flick of his wand, Severus transfigured the quill he'd been using to take notes into a tiny, shimmering bluebird. The bird chirped and flapped its wings, hopping around in odd patterns on the tabletop, and Hermione's eyes widened in awe at the rather delicate display of magic. Though she still maintained a sceptical expression.

"That's rather impressive, Snape, but it's still transfiguration."

With nothing more than a smirk, the wizard uncorked the vial, carefully releasing the dark substance within over the bluebird. Almost instantly, and before Hermione's disbelieving eyes, the creature's movements became more fluid, its colours brighter, and an unmistakable vitality filled the room as the inky darkness seeped into the bird's feathers and skin.

The witch gasped, her scientific mind warring with the very real, very magical spectacle before her. "You... you brought it to life," she breathed, looking to Severus with eyes filled with wonder.

Severus just smirked, a triumphant glint appearing in his own eyes. "Alchemy and Transfiguration, Granger. Two sides of the same galleon."

"B-but that's dangerous! Unpredictable!" Hermione suddenly exploded. "What if the magic goes awry?" she continued, her concern for the ethical implications of such an experimentation etched within every line that had appeared on her forehead as she looked back to the bluebird.

A raven eyebrow arched. "Magic is inherently unpredictable. We are but wayfarers navigating its currents, with only those of us skilled or strong enough able to harness its power. The boundaries you seek to maintain are nothing more than self-imposing limitations."

That had Hermione's mouth snapping closed, whatever retort she'd been about to spew dying upon her tongue. She hesitated, torn between her logical reservations and the undeniable allure of Severus' revelation.

"But... why keep this knowledge hidden? If what you say is true, it could revolutionise the way we understand magic as a whole."

Severus approached her, his gaze intense. "Because, Miss Granger, knowledge is power, and not all are equipped to wield it responsibly. Imagine the chaos if every wizard and witch were to dabble in such matters without understanding the consequences."

"Consequences?"

The wizard paused in his approach, dark-brown, almost black eyes scanning the witch's features, searching for something only they knew.

"What do you know of Obscuri?" he suddenly questioned, turning away from Hermione as if he were about to return to his chair and the specimen he'd been studying, missing how her eyebrows furrowed, clearly caught off guard by the sudden shift in conversation. Though he also didn't need to see to know that they had.

Severus knew that if there was one thing Hermione could never let go of it was her incessant need to reveal every fact she'd learnt on a topic. The wizard swore he still had nightmares of marking her schoolwork - all thirty bloody feet of it.

"Obscuri? Well, they're dark, parasitic magical entities that form when a young witch or wizard suppresses their magical abilities due to fear or trauma. The magical energy, unable to find an outlet through the host, turns into a destructive force, wreaking havoc wherever it goes."

"And what if I told you that you were wrong?" Severus questioned as he turned back to the witch with a rather serious expression. "What if I told you that an Obscurus is instead the very magic of the witch or wizard in question; magic that had chosen to go rouge?"

"But- that's..."

Severus nodded; his gaze intense. "Precisely. An Obscurus is not a parasite, but in fact a manifestation of a host refusing their magic, and in turn, magic refusing their host. The result is and 'outburst' of this rouge magic - the 'essence' of the witch or wizard who had refused it." He paused, as if gauging his partner's grasp on the topic before continuing. "But magic, as you know, needs a host. An Obscurus, once separated from its person, is a dying entity. It craves a connection, a vessel through which it can thrive - and this, Granger, is where my experiment takes a turn."

Hermione's eyes were wide as they snapped up to meet her partner's, disbelief written across her features. "You used an Obscurus in your experiment?! But they die once they leave their host!"

"Yes, I believe I just stated that," Severus deadpanned, even as a mixture of pride and caution swirled within his eyes. He was proud of what he had discovered, no doubt, but what he was revealing was something he never even told the great Albus Dumbledore. Severus had no reservations that the former Headmaster of Hogwarts could - would - have been worse that Voldemort if he'd know the secrets behind his own craft.

The once-Death Eater Spy was certain that if Dumbledore hadn't been blinkered by his own motivations behind needing the Deathly Hallows in order to become the 'Master of Death', the wizard would have realised what he's been after had been under his nose the whole time. He wasn't certain as to how far Dumbledore would have gone, but there was this nagging feeling in the back of his mind that told Severus the former Transfigurations Master and Headmaster of Hogwarts would have used his own nephew's essence to bring back his sister if the knowledge had been presented to him at the time.

Giving himself a mental shake, Severus' attention returned to the present. "However, what if I were to reveal that it were possible to redirect that dying 'essence', utilise magic's desperate need for a host and redirect it towards a different recipient?" he continued, even as his eyes drifted to the bluebird now fluttering about their workspace; a bird who'd once been nothing more than a feather he'd been utilising to write down the notes of their experimentations, yet was now flying about with a vitality that radiated with the mysterious miracle that was life.

"An Obscurus, transfigured from the remains of a deceased magical creature, becomes something like an animating force - a 'soul', if you will - that binds with the flesh of the transfigured bird," he explained. "It's a delicate balance, a dance of magic and mortality."

"You-you created an Obscurus? Severus, that's Necromantic Magic - forbidden!"

The wizard frowned, eyeing his partner with a look that wasn't entirely friendly. "Of course that is what you got from my explanation," he muttered under his breath with an eyeroll before deciding to just 'bite the bullet'.

"Look, Granger, what I'm about to reveal is not common knowledge, and for good reason," he begun, adding, "And before you're head goes and explodes on you, I'm only doing this because our Oath as Unspeakables stops us from revealing our work to others outside this department," as he watched the way the witch's eyes lit up with the possibility of learning one of Severus Snape's secrets. "The essence I used in this experiment was that of an Obscurus, yes. But, it was one that had been transfigured from the remains of a deceased magical creature - an bluebird, in this case."

Hermione, although having been awed by the magical feat before her, couldn't help but voice her concern. "But what does this have to do with Transfiguration or Alchemy?" she asked, "It honestly sounds more like the Dark Arts than anything else."

A raven brow once again raised upon Severus' forehead at the witch's observation, and his tone was measured as he replied. "That, Miss Granger, is wherein you're mistaken. Magic is neither light nor dark, but grey. We as humans think it is wrong to kill another, even with good reasonings. Yet can we also say that it is wrong for a magical being to deny the magic they'd been born with the release it so desperately craves? There is a reason the Ministry just doesn't up and obliviate repeat offenders and ship them off to the Muggle world."

"Though back to the Obscurus," the wizard stated, drawing the conversation back to safer territories as he noticed Hermione's jaw tick with a half-hidden grimace. The pair may have worked together for more than a few years after the war, but Severus knew there were still subjects that were still touchy to broach upon; obliviation being one of them. "My experiment aims to bridge the gap between Transfiguration and Alchemy. The transfiguration provides a vessel - a lifeless object transforming into that of a living creature. The alchemical aspect, however, lies in the redirection of the obscuras magic, turning what had once been a rebellious and dying entity into a source of life."

Severus paced a few steps away from Hermione, his robes trailing behind him. "Imagine, if you will, the implications. Not only could one turn a toothpick into a chicken in order to eat, but this process also offers a potential solution to save the magic that has been rejected by their host - a 'second chance' for what was once condemned to wither away."

"But why keep this hidden?" Hermione interjected, torn between fascination and moral qualms. "Why not share it?"

Dark-brown eyes became even darker as pain and regret flashed across Severus' features, and his voice was but a soft rumble through the air as he admitted, "Because knowledge of this magnitude is like a double-edged sword. If the Dark Lord had known how simple it was to create life, to just transfigure himself a new body and then redirect his own essence into its form, he wouldn't have needed Horcruxes to secure his immortality. My discovery of the Obscurus Potion was a product of his already relentless pursuit of Dark Magic. He had heard of what Grindelwald had tried and failed to do, and forced me to delve into these secrets. However, even I couldn't have known how invaluable this knowledge would have proven to be to him if he had discovered it."

Hermione just raised a questioning eyebrow, clearly needing further explanation, and Severus paused, letting the weight of his words first settle in the air before continuing. "In my research, I discovered that not only would the Dark Lord have spared himself the need for Horcruxes, but he also could have discovered a way to manipulate magic, to, in a sense, take it - steal the magic from another person."

A gasp of horror left Hermione's lips as the last words left Severus' lips, and her eyes widened at the implications of what he was suggesting. "Stealing magic? But that's... that's unthinkable!"

"Not entirely," Severus argued, levelling the witch with a knowing look. "Have Purebloods not claimed that Muggleborns have been doing the exact same thing for centuries? Who is to say that their claims are not based on truth. Could it not be reasonable to say that an Obscurus, the 'essence' of a dying and rejected magic without a host, could not have stumbled upon a pregnant Muggle woman, and finding her babe just the right size and type, deciding that they would be perfect for the Obscurus to inhabit? Ollivander has always quoted that the wand chooses the wizard, why could the essence of rejected magic not do the same?"

"The essence of magic, Granger, it's an elusive force," the wizard mused, watching as a contemplative expression stole its way across his partner's features, recognising the storm of thoughts brewing within that brilliant mind of hers. "Alchemy's First Law of Equivalent Exchange-"

"-Humankind cannot gain anything without first giving something in return. To obtain, something of equal value must be lost," Hermione cut in almost automatically, and Severus shot her a look.

"Yes," he drawled slowly. "I am aware," he added with a tight upwards twitch of his lips before continuing on from what he'd been saying before he'd been cut off. "Alchemy's First Law may hold true, but what if we could redefine the terms of 'exchange'? Transfiguration, it offers a glimpse into the transformative power of magic, and the Obscurus Potion I created is able to redirect magic's very essence, given what would have once been lost or wasted a new purpose - a new life."

Hermione, caught between fascination and moral concern, pressed on. "But what about the potential misuse? If this knowledge fell into the wrong hands..."

Severus nodded solemnly. "What, indeed. The potential for misuse of such knowledge, well..." his eyes drifted to the bird still flittering about their workspace. "There is a reason the Ministry is still investigating the possibilities."

"You haven't shown them, have you?" Her mind racing, Hermione couldn't help but add on the question that had been gnawing at her since its revelation, utterly gobsmacked that Severus would have shown her something he hadn't even shared with their very employers yet. "But, what about your potion? How is it different from a... well, come on Severus, if it essentially captures the 'essence' of a magical being?"

Her partner's response was measured and contemplative in its own right, Severus taking his time to reply. "How it differs from a Horcrux, as I'm sure you were referring such a potion to, lies in the nature of what is captured. A Horcrux is created by anchoring only a piece of the soul, a fundamental aspect of a person's identity. Yet the Obscurus Potion captures the magical essence, the 'energy' that permeates a magical being. It is created from the crux of magic, not a piece of a soul."

"And consider this, if you will," he continued, "In the realm of families and bloodlines - does this not already occur; the 'preservation' of magic? The genes of two people, are they not being replicated or 'saved' within their son or daughter? The passing on of magical abilities, the inheritance of traits and magical potential... it is but an age-old process that has been occurring since we decided to descend from the trees and start wielding sticks, and one that is not that dissimilar to what my potion has unintentionally stumbled upon."

"But what does this have to do with Transfiguration, Severus?" Hermione questioned, stumped by the complexity of the revelations being laid upon her and trying to turn the discussion back to what it was that had first started it. "It seems we've ventured far beyond the realm of changing one substance into another."

Her partner could only acknowledge her point with a nod - before completely throwing her for another loop.

"True, it doesn't directly relate to Transfiguration. However, does it not underscore the interconnectedness of various magical practices, including Transfiguration?" He leaned in, fixing her with an intense gaze. "Think on this, Miss Granger: when a magical person dies, where does that magic go? It dissipates into the air, lost to the world. The Obscurus Potion, in its essence, captures and redirects that magic, giving it a new purpose, a new life."

The wizard smirked as he gestured towards the now-living bluebird, once a mere feather of a magical owl. "This transfigured bird is not 'alive' in the conventional sense that it broke into the world through that of an egg, but it is still undeniably 'living', is it not? Does it serve not as proof that life - or a chicken - can indeed be created from a toothpick?"

As Hermione grappled with the profound implications of Snape's words, she couldn't shake the feeling that they were on the precipice of understanding magic in ways that transcended the conventional boundaries of wizarding knowledge. The blurred lines between alchemy, transfiguration, and the essence of magic itself had led them into uncharted territory - a realm where the secrets of life and creation were written in the language of spells, potions, and the very fabric of the Magical World.

Fin...