Tried to tweak the story but managed to frazzle the format so bad I had to reupload. Oh, boy.

First and foremost—

Trigger warning:

This piece of fiction will undoubtedly contain a May-December (age difference) romance between two very dark, very twisted people. Tom, at the meeting point of the story, is seventeen—the legal age in the wizarding world. Keep note: Tom is a very self-aware character and, by the year 1943-1944 this is set in, has: set a deadly beast upon a school full of young children, indirectly killed Myrtle due to prejudiced views, murdered his own father, grandparents, incarcerated his uncle, and split his soul twice, damning himself to limbo.

'Lusting' over an older, malicious wizard isn't the worst thing a younger Tom Riddle could do, folks.

Also.

This story, if it's not obvious yet, is very, very self-indulgent, for I have scrapped Gellert's portrayal in the Fantastic Beasts films almost completely, sans: him being a seer(?), his armies, his rallies, events, his (past) fixation on Credence, relationship with Dumbledore, and Vinda Rosier.

In the earlier drafts for this fanfic, before the movies had come out, I had imagined Gellert to be much like Tom, in a sense. (Can't trust Johnny Depp's edgy Game of Thrones debut to woo the likes of Albus Dumbledore, to be honest.) So, having said that, I would like to warn that, in this work, Gellert tries to use his image and charisma and charm to gather and retain his followers, hence him appearing way younger in this story than he is during the time before the 'Greatest Duel'.

(Yes, I am making Gellert Grindelwald Michael Langdon level pretty, just to rub it into Dumbledore's face, and just because I can—let me live, guys.)

Rating may jump up to M (undoubtedly) in later chapters. So, if that essay or any of its contents hasn't scared you off, I hope you enjoy my application for a mid-level seat in Hell!

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PARIS, FRANCE

november 19th, 1943.

.

It is Rosier who dooms him at the start.

Or, rather, it's his blubbering mouth, stained with vintage Pinnock and chipped off skin that tries to impress his most regarded family member.

(In retrospect, it was Tom's fault; he should have paid more attention to who the dim-wit was related to and just how loose-lipped and stammered he became after three flutes of champagne during their Slug Club parties.

Though, in hindsight, he could have just stepped on Arthur's throat harder before he left for France after their Potions' class; hard enough to make his eyes gauge and his skin blotch and his head smart enough to know better.)

But Arthur turns seventeen, and no matter how foolhardy or dumb Rosier is, his family is pure-blooded and prominent, and on the right side of the only war that mattered to their kind. Spirits were high, and even the tiniest occasion called for celebration among the Alliance—even as tiny and insignificant as Arthur Rosier's birth.

So, as muggle Paris shrouds in darkness and fear and silence, toasts and laughs are shared in between flutes of champagne inside the walls of Rosier manor, and Arthur couldn't be happier.

He shakes his clammy hand with anyone who is bothered enough to remember, formally, why they were there—to celebrate the Lieutenant's nephew's birthday—and stammers his way through the small, disinterested crowd gathered around his anxious form that starts to disperse.

Arthur cards his shaky fingers through gelled, dark locks as he tries to reinstate the attention of his beautiful, gorgeous, way-out-of-his-league childhood friend—acquaintance, she sharply corrected her father upon introduction—Bernadette, with tales of Hogwarts mischief and Slytherin valor. But all the girl cares for during his French blunder is if her pearly whites are unstained with cherry lipstick and if her honeycomb hair is anything but meticulous and has Pierre done talking to Francesca and—

"So, uhm, your Father did mention we would be, that is to say—uh, a good match for marriage, if you'd, well, be willing to entertain the thought?"

At that, Bernadette whips her head in his direction,—hairdo be damned!—a vicious scowl marring her heart-shaped face, and Arthur feels like swallowing down his tongue.

"I've already told you, Archie. If you're not Pierre Delaghni, I won't ever lay a hand on you! You're just a hideous nobody who thinks tha—"

"—Ehem."

The room grows silent and chilled, and Bernadette throws her head back a second time that night. Before the red-faced, humiliated Arthur stands his aunt.

His wonderful, famous, powerful aunt.

Vinda Rosier still looks just as regal and elegant at the cusp of her youth as she did in her glory days. Although many in the room would argue that her golden age has not yet ended, for two decades later, Vinda still serves as the right-hand woman to the most powerful Dark Lord to grace the Earth. And Arthur feels privileged to share a name with someone of such great stance and poise and status.

She wears robes of deep green chiffon, signature hat amiss from her raven strands. She does not look a day over thirty, in his opinion, but Arthur never voiced that curious fact.

(After all, he has heard enough of his envious Mother whispering about her husband's devious sister and her adamant need to retain her youthful appearance.

"The woman always has the need to seem younger than she truly is," Angelique Rosier had sneered as she spewed green to her cousin. "Maybe Grindelwald likes them young—heard he's trying to save face in the same way, as well!")

"Madame Rosier!" It strikes a cord deep within Rosier that Bernadette so quickly changes her tune at the appearance of his aunt. "How lovely it is to see you again! I do sincerely hope you still remember me fro—"

"I would like to speak with my nephew now, if you will."

Bernadette emits a strangled sound, and Arthur feels a slight smirk grace his dry lips as Aunt Vinda comes closer to him, completely disregarding the young French witch.

"Dearest Arthur," she purs as she pulls him into an embrace while Arthur wills his knee to stop shaking. "You're finally of age."

Vinda steps back, lips scarlet and twitched. Arthur swallows the saliva gathered in his esophagus, taking in the slightest wrinkles crowning the sides of her cool, steely eyes.

He has always—always—idolised Aunt Vinda. From the first time he saw her perform magic at the tender age of four, to realizing just what her true standing was in this world. Vinda Rosier is at the top of the food chain, and even though she does not publicise her family's name, Arthur feels a sense of superiority when he stands here, in France, where he is an extension to her might and reputation.

However, at Hogwarts, that sense of distinction dwindles in the form of Tom Marvolo Riddle. Arthur, at first, did not comprehend why he hadn't don pale blue silk as a student of Beauxbatons, but a single sentence from his Father had locked his mouth shut.

(It's what Aunt Vinda wants of you, he had said, and who was Arthur to refuse his renowned family and their wishes?)

Problem is, at age seventeen, Arthur still does not understand what the purpose of him being at Hogwarts is. He does suspect, however, that it has something to do with his lofty and snooping Transfiguration Professor—Albus Dumbledore.

His aunt often asks about him as well, however subtle it may be. Vinda, apparently, did not trust him nor her own brother with the details. And, as predicted by the acolyte herself, Arthur does not pay much attention to Dumbledore's doings and extracurriculars that do not intervene with anything Riddle cooks up that day, so the only thing he can say, in a meek and embarrassed voice, is: he's giving Tom a hard time, as usual.

But Aunt Vinda is not discouraged by her nephew's hero-worship of the orphan boy, for the fact that Albus Dumbledore despises a student is fascinating to her. She had enquired about the boy, about his blood status and his skills, and when Arthur confirmed both to be above the norm, Vinda catalogued Tom Riddle to be a worthy enough name to remember in their conversations.

"So glad you could make it today," Vinda says in a warm enough voice, but Arthur's gut feels icy.

This party would have happened with or without me, Arthur acknowledges glumly as he snatches a passing by flute. It's just a happy coincidence that it's my birthday today.

And he is right; everywhere he turns, he sees banners fluttering in midst of portraits and burgundy wallpaper, bearing a symbol comprising of a wand piercing a decorative circle, eclipsed by an elegant triangle and harsh brush strokes.

The sign of the Alliance.

The sign of Gellert Grindelwald, the darkest wizard of all time.

Arthur feels uneasy at the display.

He downs the liquid, and the burn of it colours his mouth with courage. "Wouldn't have missed it for the world, Aunt Vinda!"

"Good," Vinda sounds pleased. "We have so much to discuss, my dear."

Even though Arthur and his parents don't hold a concrete stance in the war Vinda actively participates in and supports, they flounder in the wealth and prestige it brings to the house of Rosier. So, with the implication and promise hanging above his head, Arthur follows his aunt to a much more secluded wing of their home, picking up another glass of champagne on his way.

I'll need this, Arthur thinks as he grips the stem harder.

When they reach the guest room Aunt Vinda stays in on the rare occasions she stops by, she casts a silencing charm over the lavish walls.

"So, tell me, Arthur—how is school going?" Vinda starts light as she reclines upon an armchair across from the shifting Arthur, and he tries to resists the urge to squeeze the glass firmer.

"Hogwarts is, uh, fine, I guess," Arthur replies, uncertainty clouding his tone. "Things are going back to normal—with what happened last year, you know."

But Vinda doesn't know, and her sharp eyebrows arch in interest.

Arthur wants to kick himself at that; neither he, nor his parents had seen the powerful witch since last spring, for Grindelwald had launched a campaign amidst the Italian wizards for almost half a year in rapid succession.

(Arthur realizes that, indeed, his birthday correlates with Grindelwald's victory over the Ancient Roman mage guilds, hence the Italian he kept hearing in the main hall.

He feels pathetic even entertaining the thought that this celebration was about him in the first place.)

"Well," he fumbles with his words, switching to his more familiar English to describe the events of last summer. "A muggle-born had been murdered by an unknown monster and the school was due to shut."

"Oh, really?" For the first time in a long while, Arthur sees Vinda surprised. Arthur isn't sure what caused the unfamiliar expression: the fact that nobody from the Alliance saw fit to inform their superiors of Hogwarts nearly shutting its gates for potential future followers, or the fact that something—or someone—got away with murdering mudbloods under Dumbledore's nose. "Had they caught the beast?"

"Uhm," he stutters. "I think so, yeah. I mean, Riddle says this smuggled Acromantula was the cause of the murder, and the faculty expelled the student that got it inside Hogwarts in the first place—"

"—But you have your doubts." Vinda finishes his sentence, shrewd eyes glinting in the newly-lit firelight, and Arthur isn't sure that's what he was about to say.

"I—" he struggles to find his voice, downing another flute of champagne to ease the words to come, cringing. He places the empty glass atop the nearby coffee table, running his hand across sweaty brows. "I don't know, Aunt Vinda. Tom's been acting all types of strange since last year, and Dumbledore's been riding his back since summer break ended."

"Oh?" Vinda tilts her head, lacing her gloved fingers together as the discussion shifts, yet again, to the Riddle boy. "Is Albus giving the poor boy trouble again?"

Arthur feels the alcohol start to enter his bloodstream, hears it rushing through his ears and cloud his brain. He barks a short laugh in frustration and recollection. "Bah! You can say that again! Riddle even said that he suspects him, Auntie! Absurd!"

But Vinda doesn't share his humour, or his blind-sighted loyalty to this teenaged genius who's managed to foster the rare ire of Dumbledore. No, Vinda tucks her chin beneath her entwined digits in silent thought, all the plans she wanted to bring up to her sub-par nephew dispersing for a moment of cold wonderment.

"Arthur," she suddenly starts gently, habitually, and Arthur listens keenly. "Has this Tom Riddle ever expressed his views on Grindelwald to you or anyone around him?"

Arthur's mind reels.

His lips part and close repeatedly, at a loss for words at her question. But Vinda extends her hand for him to take, and Rosier can't remember the last time he felt this much focus on him from his aunt. So, his drunken mind starts thinking; thinking of the countless discussions Tom has had with Abraxas about blood superiority, how Riddle had suddenly changed his views to match Malfoy's since last Christmas.

Tom wasn't a big fan of muggles to begin with, but he never spoke about muggle-borns being inferior to pure-blooded wizards.

Until recently, that is.

Since Tom got his hands on several tomes Arthur knows to have belonged in the restricted section, he's done a half spin on the sole of his foot. Whatever Tom had found in those pages had morphed his opinions quite a bit, and Arthur can't say as to why.

However, Tom has never been a follower; rather, he is the leader of the pack, a prime example of excellence and talent. Arthur chews on his bottom lip as he thinks of Riddle's nature, and how joining a force that isn't his own doesn't seem like an option the orphan boy will ever consider entertaining.

But then Rosier's eyes trail from the expectant face of Aunt Vinda to the opposing symbol hanging above her head, older than any hanging in the ballroom a wing away, and a memory soon clicks into place.

"He's not a fan of muggles—or muggle-borns, for that matter. But I don't think he's ever really talked about any of the wars going on." Arthur rubs the back of his neck. "Besides the Blitz; that's the only thing that actually affects him, I think."

He pauses, suddenly at a loss, yet Arthur feels the encouraging squeeze of Vinda's bony fingers grasping his hand, and the words rush out on their own involuntarily, the alcohol untying his tongue.

(And that's the moment Tom Riddle's fate seals shut.)

"However, I've seen him wearing this ring since September. Nothing special; an ugly thing, honestly." Arthur closes his light eyes, trying to recall the imposing design resting about Tom's slender finger. He snaps his own ones once, twice, before finally remembering the cause of unease. "But it had the sign of Grindelwald on it! Well, er, the old design, anyway, carved on a dark stone. Triangle, line, circle. Just like the one on the prototype banners you've shown me once"

And then Vinda's hand goes slack, her face shocked.

Arthur's flushed cheeks stretch into a grin; proud and ecstatic that his drunken self seemed to do something right!

.

HOGWARTS, SCOTLAND

november 21st, 1943.

.

Oh, if only he had a time-turner.

Tom is going to kill me, Arthur thinks, back leaning against the cubicle door. He clutches a handkerchief to his mouth, puke staining the light linen material.

He tries to breathe.

C'mon, Rosier! He doesn't know a thing!

But a tiny voice in his head can't help but whisper, feeding his paranoia:

(Yet.)

No good; he's hyperventilating now.

His body falls into another bout of nausea and cold, tingling panic as the realisation that Riddle is probably waiting on him right now hits.

When he climbed out of the Floo Network half an hour prior, he blamed international transportation and too many toasts on his weakened stomach. In reality, the overwhelming dread and numbness is caused by his aunt's darkened glint, the whispers that followed, and his sobering mind clicking together just what had transpired the night before, and the implication of it.

("W-What are you planning to do, Aunt Vinda?" Arthur's voice had cracked the following morning, recollection painting his face a sickly pale colour.

A gloved hand pinched his cheek, then, flushing the spot an angry, scalding red in turn.

"Do not fret, Arthur. Everything is going to be alright.)

Except, it won't.

Even if he adores his aunt, he is not oblivious to the cold frost lying beneath her skin and flesh. She couldn't have held her position as Grindelwald's right-hand-woman with kindness and honesty for so long, after all.

No, Arthur realizes he's finally ended up on the other side of Aunt Vinda's blade.

What should have been a harmless, skidding gossip session with his disinterested aunt about school and Dumbledore and marriage candidates turned into what might potentially become the doom of the most dangerous boy he's had the honor of meeting.

Because Tom doesn't know.

He doesn't know that Arthur shares ancient blood with one of the most powerful witches of the 20th century—one that closely entwines herself with Grindelwald and his battles. He doesn't know that his 'small family get-togethers' translate into one of the biggest Grindelwald's Alliance meetings in Europe; the ones that actually matter.

Tom is not aware that Arthur has made him into a red-hot target for whatever Aunt Vinda had picked up during their conversation that prompted her to want to know the boy so personally.

(And Arthur told her everything.)

But he will make sure Tom never knows of this betrayal of details, for he doesn't doubt Riddle will skin him alive. Rosier knows he's capable of it; knowing that Dumbledore is somehow important to Vinda and, in extension, Grindelwald, his professor's wariness and distrust and coldness towards Tom might just speak volumes, as his face only turns that stony when listening to the news of carnage and despair caused by the dark wizard.

He never feared Aunt Vinda, in truth—but Tom truly terrifies him.

Yet—

He gets his bearings together, feeling the potion which Slughorn had graciously handed to him as he stumbled from the fireplace take effect and clear the storm brewing in his belly, and shifts to get up on his polished shoes.

If it's one thing that Tom hates more than insubordination, it's tardiness, and Arthur is not about to raise any more attention to himself than he has with him leaving the castle for an exclusive weekend party in Paris. So, he gets up, pats his dry lips once more, and shakes his head to clear his thoughts of various what-ifs and would-bes.

Plus, Arthur thinks. By the time Riddle will be off Hogwarts grounds by next year's summer break, Aunt Vinda will have fully forgotten about any mentions of rings and symbols.

But Rosier's reassurance proves to be incorrect as he enters the Slytherin common room, and he wants to disappear into the floor.

"What do you mean?" Rosier hisses at Abraxas Malfoy, who clambers his mouth with bejeweled fingers.

"Exactly what I said," Abraxas whispers back, a few strands of long, platinum hair escaping the string lacing his braid. "Dumbledore and the rest of the faculty are not allowing Riddle nor anyone else to stay over on Christmas break; something to do with safety procedures due to last time."

Last time. The mudblood. The monster.

Tom.

Arthur gulps as he shuffles closer to the fireplace, where an enraged figure sits still upon a velvet armchair.

Arthur surveys his form; face taut, eyebrows furrowed, slender fingers cradling a tense jaw—Tom Marvolo Riddle is not pleased. His dark grey eyes suddenly shift towards the newly-arrived Arthur, and Rosier can't help but cast his gaze down.

"How was it?" Tom's muffled question comes from in between his fingers, and the movement causes the ring resting against pale skin to glint.

Arthur wants to go back to Paris.

"G-Great, uhm," he stutters, feeling as if he is in Vinda Rosier's presence once more, but worse. "Same old; Bernadette w-was there, too."

He hopes that, at the mention of his infatuation, Tom would drop his suspicious stare off his face, yet that only spurs him on as he leans further back into the headrest.

"Well? Has she accepted your proposal for marriage, then?" The question weighs Rosier further down, for that was the excuse he gave the sullen boy as to why he needed to be present in the Parisian festivities.

"No.." Arthur's voice trails off as he figures blaming his shiftiness and nausea on rejection-spurred binge drinking to be the safe option. He picks his eyes up to survey Riddle's reaction, but is incapable of holding his stare for too long.

Rosier looks at his hand instead.

(What's so special about that ring, anyway?)

Tom regards him for a long moment, drinking in his words before ultimately dropping the subject.

He had more important things to contemplate than the buffoon Rosier and his silly family affairs. One of them being: patrol reports, Dumbledore, and his pseudo-meeting with said professor after classes tomorrow.

As his tongue slowly clicks in displeasure at the thought, Tom slowly stands from his seat, and the surrounding boys shift back as to let him pass without uttering an unnecessary word.

All of them—Rosier, Malfoy, Nott, Avery, and Lestrange—know what happens when Tom shifts his rage at them.

They are not willing to risk it.

So, as the dark-haired boy steps out of the common room, none of them dare follow his retreating footsteps. They stay silent for a moment more, making sure Riddle is well out of earshot before turning their attention to Arthur.

"Offer Tom a place to stay," Nott says, shoulders stiff and tense still.

Rosier jerks at the words.

It's become a ritual for their group to offer Riddle solace in their family homes instead of the orphanage he stays at during the summer, all of them wanting to up one another in Tom's good graces and favour.

Yet he always declines, not wanting to depend on anyone or anything.

Still, even knowing that Tom is most likely to refuse, Arthur does not want to even risk a chance of him actually accepting and coming into contact with any of his aunt's goons.

Or, worse: Vinda Rosier herself.

So Arthur makes up an excuse—family friends staying over for the holidays—and Tom responds cordially over toast and eggs the following day, never even entertaining the Rosier Manor as an option to stay at in the first place.

(Arthur's heart finally calms from the constant staccato he has endured ever since he had woken up after the party, knowing Riddle will never come face-to-face with his scheming aunt or Grindelwald's followers.)

However, the after-class meeting with Dumbledore does not go in Tom's favour, and come Christmas break, Riddle is stranded in war-torn London, with no protection over the falling bombs, no outlet for his burning rage, and no wand to fend off what Rosier had brought down upon him.

The fact that both Tom and Gellert had Rosiers in their service at the same time will never not be funny to me.