Hells Replacement (Marin to Helltaker Demon TF)

The convention hall buzzed with energy. Wings, horns, capes, and weapons of every kind cluttered the aisles. Judgment walked stiffly through the crowd, tugging at the collar of her sharp judicial robes. Her expression, as usual, was grim.

Lucifer strolled beside her, practically glowing, her black suit and crimson tie immaculate. She smirked as attendees pointed their phones at her, whispering “Amazing cosplay!”

Judgment groaned.
Judgment: “I hate this. We put on our actual work clothes, and somehow, we still blend in. That’s… depressing.”

Lucifer: chuckling “Oh, come now. At least it saves us from awkward questions about authenticity.”

They stepped aside to let a group of armored cosplayers pass, Judgment’s scowl deepening.
Judgment: “We shouldn’t even be here. You abandoned your post, and the others followed. Hell is half-empty, barely functioning.”

Lucifer: shrugs “Ever since our darling took us in, none of us have really… kept up with the old job. Can you blame them? It’s more fun topside.”

Judgment: sternly “That’s not the point. What happens to Hell without its ruler? Without its demons? You’re supposed to—”

Lucifer: interrupting, snapping her fingers “—which brings me to my genius plan.” Her grin spreads. “We find someone down here, an eager human. Someone who already loves the demon aesthetic. Offer them the contract, hand over the role, and voila! I get to stay with Darling, and Hell gets its ruler back.”

Judgment: folding arms “That’s irresponsible. You’d hand the throne to a mortal girl just because she likes horns and fishnets?”

Lucifer: smirking sideways “And you’re any better? You’re here in costume, enjoying the break like the rest of us.”

Judgment’s eyes narrowed, but before she could retort, Lucifer’s gaze shifted past the crowd. Her smile sharpened.
Lucifer: “…Well, speak of the devil.”

For the first time all day, they saw her: a tall, blonde girl laughing with her friends, decked in a striking succubus cosplay. She had bat wings, horns, thigh-high boots and a red wig in her hand. And whenever the crowd came closer, she put on her full costume again and posed energetically for pictures.

Lucifer tilted her head, amused.
Lucifer: “First demon cosplay we’ve seen all con. And look at that enthusiasm. Perfect.”

Judgment sighed, already regretting this.
Judgment: “...THAT is who you want to run hell?”

Lucifer: grinning ear to ear “Exactly.”

She moved through the crowd with predatory grace, brushing shoulders until she reached the tall blonde succubus cosplayer.

Lucifer: sweetly “Excuse me, darling. Could I borrow a moment of your time? I have something… very special to show you.”

Marin blinked, then lit up like a firework.
Marin: “Whoa! Your cosplays are insane! Like, I thought mine was good, but you two look, like, straight out of a game cutscene!”

Judgment pinched the bridge of her nose, muttering under her breath.
Judgment: “Of course she thinks we’re cosplayers…”

But Marin, delighted, eagerly followed as Lucifer guided her toward a quieter aisle away from the throngs. Judgment trailed behind, already unimpressed.

Once they were away from the noise, Lucifer clasped her hands together with theatrical charm.
Lucifer: “Allow me to introduce myself properly. I am Lucifer, the Matriarch of Hell itself, as you can clearly see. And this is my associate, Judgment.”

Marin clapped her hands together, eyes sparkling.
Marin: “That’s sooo cool! You’re totally staying in character… I mean… Of course! What else could you have been? Hehehe.”

Judgment folded her arms, glaring.
Judgment: flatly “I don’t like her.”

Lucifer waved her hand dismissively, refusing to let Marin’s disbelief spoil the mood.
Lucifer: “Now, listen closely, dear. I’ve grown… weary of my duties. Endless torment, eternal paperwork, you understand. So I seek a replacement. Someone young, energetic, and unafraid of demons. Someone like you.”

Marin: grinning ear to ear “Oh my god, that’s, like, perfect! I’m definitely not afraid of demons. Look at me, I’m literally dressed as one! This is the best roleplay I’ve done all year!”

Judgment’s glare sharpened.
Judgment: “She doesn’t believe a word of this.”

Lucifer shot her a warning glance and pressed on, keeping her tone honey-sweet.
Lucifer: “Splendid, splendid. Then let us make it official.”

She reached into the air and pulled forth a glowing, fiery scroll that unfurled itself with ominous weight. The parchment glowed crimson, its letters writhing like living flame.

Lucifer: “Sign this contract, and you shall become a true succubus. Greater than any mortal costume could capture. And for a time, you will rule Hell in my stead. Until, of course, I return.”

Judgment muttered, arms crossed tighter.
Judgment: “…And I wonder when that’s going to happen.”

Marin, still giggling, leaned forward to study the scroll.
Marin: “This is amazing, you even made it glow! You guys went all in. Okay, sure. If it means I get to be the ruler of Hell, then I’ll totally make a great one!”

With a dramatic flourish, she scribbled her name across the burning parchment.

The scroll snapped shut with a burst of flame. Lucifer’s smile widened.
Lucifer: “Excellent.”

The fire leapt from the parchment and crawled up Marin’s arms like living ribbons, twisting and coiling, then bursting outward to engulf her whole frame. The crowd of heat and light wrapped her like a second skin, seeping into every pore.

Marin: laughing nervously at first “Haha… whoa! This is… actually kinda warm—”

Her words caught in her throat as a pressure surged inside her chest, like her body might burst from within. She gasped, staggering, but the flames only danced faster, spiraling higher.

Slowly, impossibly, Marin began to grow. Bit by bit, her already tall frame stretched taller, rising past the heads of the convention-goers. Her posture straightened, her back lengthened, and soon she loomed at nearly one-point-nine meters, her proportions reshaping into something regal, commanding, almost inhuman.

Heat swelled in her chest. Marin clutched herself, eyes wide as she felt her bust expand against the thin fabric of her costume. The padding she had stuffed in earlier became laughably unnecessary as her body overtook it, filling out and swelling further still. Her cleavage pushed higher, heavier, rounder, coming nearer and nearer to the impossible figure she attempted to cosplay in the first place.

Her hips shuddered as her backside rounded, growing lush and firm, her thighs thickening with sculpted curves. Every second pulled her further from “cosplay trick” and closer to the impossible perfection of a succubus made real.

Then came the rumble. A deep, trembling quake in her stomach. Marin gasped, clutching her middle as it tightened like a bowstring. Her soft belly hardened in an instant, muscles snapping into sharp relief. A defined six-pack pressed boldly through her skin, while her arms and legs followed suit, rapidly becoming toned, chiseled, and carved with power.

She flexed instinctively, and the strength humming under her skin nearly overwhelmed her. It was as though her veins ran molten with energy, every fiber of her body pumped full of infinite, intoxicating power.

Marin: between startled laughter and wild awe “Oh my god… this feels… insane!”

Lucifer materialized and  swirled the glass of wine in her hand, as if she’d been holding it all along.
Lucifer: with a smirk “And it’s only getting better, darling.”

The fire around Marin flared brighter, then sank into her skin. A rush of energy crackled through her veins, bursting out in every direction.

Her hair shimmered like silk caught in sunlight, the tips bleaching to pure white while the roots held onto their golden blonde. Her eyes burned crimson, twin embers glowing with infernal allure.

She gasped as something tugged at her lower back, a sinuous weight unfurling behind her. With a sharp whip, a glossy demon’s tail burst free just above her newly generous curves, flicking restlessly as though alive with its own mischievous will.

Then came the horns, two sleek, curling spires forcing their way from her scalp, rising proudly above her head like a crown.

Her cosplay shuddered, threads glowing before dissolving into nothing. From the flames rose a new outfit: a sharp, jet-black business suit lined with crimson trim. The jacket hugged her bust and waist in perfect contrast, the trousers clinging snugly to her powerful legs. Even fully covered, the cut of the suit flaunted every line of her impossible figure, tailoring her into the very image of a demon queen.

The last embers faded, leaving Marin standing tall, radiant, and utterly transformed.

Marin: panting, then laughing breathlessly “That was… intense. Wait… you guys were for real?”

Judgment’s eyes narrowed, her voice flat as iron.
Judgment: “We have no need for petty things like pretending or lying.”

Lucifer spread her arms in triumph, her smile sharp and indulgent.
Lucifer: “Welcome to the team, darling.”

Marin looked down at herself, her grin stretching wide. She gave her chest an experimental bounce.
Marin: “…Not gonna lie. This is kinda awesome. Look how much volume these puppies have!”

She jiggled herself proudly, laughing like a kid at a festival.

Lucifer and Judgment stared for a long moment. Then, wordlessly, they both shrugged at each other.

—

The black marble halls of Hell loomed as familiar as ever. Lucifer walked with Justice at her side, heels clicking, hands folded casually behind her back. The guards straightened at once as they passed, bowing.

Guard: “Welcome back, Lady Lucifer. Enjoying your vacation?”

Lucifer: smiling slyly “Every day.”

They reached the great doors of her office. With a push, they swung open… and Lucifer froze.

Behind her desk sat Marin, sharp in her tailored suit, fiery horns gleaming, chatting animatedly with a lanky human boy. Papers were neatly stacked, reports filed, candles burning just so. Everything in order.

Marin: beaming “Oh! Welcome back! Do you need something?”

Lucifer blinked, taken aback.
Lucifer: “…Everything looks… functional.”

Marin: “Heck yeah it does! Or should I say… hell yeah it does? Anyway, I’ve been doing all I can, part-time. Gotta keep Hell running, plus, this pays amazing! Now I can afford even more elaborate cosplays!”

She laughed brightly, clearly proud of herself.

Lucifer’s gaze flicked toward the boy beside her.
Lucifer: “And… this one?”

The boy stood and bowed slightly.
Gojo: “Ah… my name is Gojo. Wakana Gojo. Marin’s personal cosplay creator.”

Marin flushed red, suddenly very flustered, waving her hands.
Marin: “He just… he just helps me out sometimes, that’s all!”

Lucifer’s smirk deepened. Succubi were notoriously bad at hiding their affections, and Marin’s blush told her everything.

Justice leaned in close to Lucifer, whispering with a grin.
Justice: “That’s the new chief of Hell?”

Lucifer: “Yes.”

Justice chuckled, eyes sparkling.
Justice: “Well, well, well~ She looks like a mighty fine gal, let me tell ya.”

Marin perked up at the sound of her name, but Justice was already sliding into a chair, launching into a rambling, good-natured chat about cosplay fabric, wig selection, and how Hell could benefit from themed events. Marin eagerly joined in, bouncing in her seat with enthusiasm.

Gojo and Lucifer lasted about fifteen minutes before exchanging a glance and slipping out the door.

In the corridor, Lucifer sighed through her nose, a small, jealous twist in her chest at Marin's excellence as Hell's caretaker. But more than anything, she felt proud. Proud of her choice.

Lucifer: to herself, smiling “Yes… I made the right choice. I guess that means I won’t be taking the office back anytime soon.”

—

Motto of cosplayer: Fake it until you become it.