Shirou tames a Blade Cat

The air in the small guest room hung heavy with a weight that was more emotional than physical. Rex's words lingered, a warmth counterpointing the harsh truths Shirou had finally laid bare.

"Your past doesn't define you, Shirou," Rex insisted, his large frame filling much of the room. "The man you are now, that's who matters to us. Your power, your struggle... it doesn't change the fact that you're our friend."

Around Rex, the others murmured their agreement.  Each face held a different cast of emotion – worry, concern, and above all, an unwavering acceptance that seemed almost unfathomable to Shirou.

"Thank you," he choked out, the words small and brittle in the space. It was a feeling unlike any he'd known – this simple camaraderie, this offer of understanding without needing justification or explanation.  There was an echo of Kiritsugu in it, of the unyielding ideals that had always seemed beyond Shirou's own flawed self. Yet here, with these people, a flicker of belief kindled. Maybe his borrowed ideal still had worth, perhaps it wasn't a complete delusion...

Rex, perhaps sensing the turmoil behind Shirou's eyes, squeezed his shoulder. "Get some rest, man. We can work out the rest later." With farewells and well-wishes, the group filed out, leaving Shirou to the solitude and silence of the dim room.

His thoughts whirled, a storm of self-doubt and quiet, newfound determination. Their acceptance was a strange comfort, a stark contrast to the self-flagellation he'd inflicted for so long.  For the first time, maybe he could envision a path where that acceptance didn't need to be conditional; where, even with his flaws and dangerous power, he might deserve a place amongst them.  Exhaustion pulled him into a fitful sleep, the sounds of the bustling house receding into the background.

Hours later, as the hush of night fell over the dwelling,  the door creaked open. Nia entered hesitantly, the dim light catching a worried edge on her features. She found Shirou awake, staring fixedly into the darkness.

"I, uh…" Nia began, then cleared her throat and sat at the edge of the bed. "I couldn't sleep.  Wanted to see how you were, but also...there's something I wanted to talk about."

Shirou nodded, a silent invitation. After all the revelations of the day, Nia coming wasn't a surprise. Part of him longed for this space, a space where honesty, however tangled, might find solid ground.  Perhaps this was where their paths would truly diverge, or maybe, it would be something different entirely.

"Shirou," Nia started, her voice small in the dim room, "There's something... when you used your ability, back there, with Rex and everyone...did you…" She trailed off, a mix of uncertainty and quiet dread filling the space between them.

Shirou knew. There was no point in denying it. Within the tangled mess of her memories that had flashed through his mind, he'd seen a different Nia. There had been pain, loss, and an echo of what his own monstrous nature must have looked like to an unknowing observer. He'd witnessed the birth of a Blade Eater:  her previous Driver, their desperate struggle to save his dying daughter, and the horrifying order  Nia had been compelled to carry out to survive.

He met her gaze, wordlessly confirming what she already suspected. It was a strange mirroring; this girl, so full of vibrant spirit, carrying the same kind of shadows he carried. She didn't hide the flicker of fear in her eyes, mirroring the wariness he knew must be present on his own face.

"It's alright," he rasped, the words tasting bitter. "To keep your secrets? I, of all people, have no right to ask otherwise."

Her small sigh of relief washed over him, a wave of shared understanding. Her own secrets were different in many ways, but like his, they cut deep.

"They don't know about..." she hesitated, searching for the right words. "About being a Blade, and... the rest." Her voice was laden with vulnerability, but there was a sliver of steel to it, the same defiant flame Shirou recognized in himself.

He thought back to the emptiness he felt as a child, rescued from the inferno by Kiritsugu. The man had given him ideals to clutch at, a path to pave with good intentions that masked the void at his core. He recalled the twisted form of those ideals in the future, in Archer, and the hollow resolve with which he'd shattered that false destiny.

"Nia," Shirou said, his voice softer, but laced with something newly resolute, "My past, the things I am... Rex and the others have accepted them. Or," he added with a wry twist of his lips, "are at least in the process of it."

"Your strength has come from choosing a path forward, one your own heart decided on. Even if you molded yourself in another's image, the will remains your own. Secrets can be heavy," he continued, "But carrying them alone does not mean you carry them lightly."

There was a tremble in her hands, but he noticed a subtle tilt to her chin. That defiant spark ignited a little brighter. Perhaps it was enough for now. They had too much else to navigate;  she could fight this fight on her own time, on her own terms. That too, he now understood, was part of strength.

The weight in the room seemed to lift slightly. Nia shifted subtly, and a hint of her usual spark peeked through as she settled with a sigh beside him on the bed.  With the unspoken pact forged, she seemed, even if just for a moment, able to push her darker burdens just a bit further into the shadows.

"See? All this doom and gloom, and now look at us brooding in the dark" she tried to tease, attempting to ease the tension as only Nia could.

It wasn't perfect, the strain evident in the forced cheer, but a flicker of warmth bloomed within Shirou. The easy companionship she radiated was such a strange contrast to the harrowing images still fresh in his mind. Yet, that contrast somehow made more sense than it should have.

For just a while, they talked. Simple exchanges, nothing overly serious. It was a balm for them both, a reminder that life went on even on the edge of a precipice. He learned bits about her adventures with Rex and Pyra, tales punctuated with her bubbly enthusiasm and dramatic flair. And, for just those few breaths, his own nightmares retreated to a background hum.

The conversation slowed, turning towards their impending battles. A spark of curiosity bloomed within Shirou then, something that had nagged at him since the confrontation earlier. "Nia," he ventured, "could I... well, it might be an odd request. But after having glimpsed your memories... would you consider letting me see your Blade form?"

There was a pause, then Nia blushed fiercely, the glow of the embers playing across her features. "Well, aren't you just full of surprises tonight!" she sputtered, the lighthearted tone forced. "At least buy a girl dinner first, with that sort of forwardness!"

"Ah, sorry," Shirou stammered, suddenly aware of just how his request might have sounded. "It's not like that! It's more that...well… that glimpse wasn't enough. There's power there, I felt it. But maybe if I saw the real thing, something clearer– it might help me understand how to…how to combat what Jin can do."

Nia regarded him silently for a long moment. Perhaps she, too, understood the odd duality of seeking beauty in the heart of something so monstrous. In that look, something unspoken passed between them - an understanding far beyond words.

Finally, she huffed, "Honestly, the way you word things! But...alright. It can't be helped, since you know my secrets anyway." Her expression shifted, softening. "Maybe... you have a point. And if it would even be a tiny bit helpful…"  A determined light gleamed in her eyes. With a fluid motion, she was off the bed, the space of the small room suddenly feeling smaller as she turned her back to him.

A soft golden glow enveloped Nia, casting long shadows with an almost sacred air. Shirou found himself holding his breath as the familiar outline of her human form melted and flowed.  Bones shifted and reformed, a flash of inhuman grace that made his very own monstrous transformation feel clunky in comparison.

Where Nia the Driver had been all soft curves and vibrant color, Nia the Blade was razor-sharp lines and shimmering power. Her usually playful cat-themed outfit transformed into a battle leotard that defied conventional fabrics, shimmering like liquid moonlight against skin the rich brown of polished wood. Gold filigree traced elaborate patterns along her thighs, highlighting their lean strength. Long, powerful legs ended in clawed, feline feet – lethal grace made manifest.  It was almost the antithesis of their lighthearted sparring on the deck.

Her white hair, normally bound in those familiar twin-tails, cascaded past her shoulders like molten silver, and those playful feline ears transformed, sleek and tipped with shimmering black that looked sharper than any steel. Yet, her vivid blue eyes were unchanged, blazing with life and fierce intelligence. In her hands, an ornate greatsword shimmered into existence, a weapon both ethereal and unmistakably dangerous.

For a moment, Shirou could only stare, his analytical mind caught in a strange loop. There was beauty in this form, the kind a craftsman might feel looking upon a perfectly forged weapon.  It was art that held death in its contours, elegance inseparable from lethality.

"Well…" Nia smirked, the blade resting loosely over her shoulder, "Stunned to silence again? Honestly, it feels a bit familiar.  Not so different from your expression when you met Mythra, you know?"  Her tease pulled him back to the present.

He felt heat prickle at his cheeks. "Don't say things like that," he muttered, but a small smile quirked at the corner of his mouth. Despite the gravity of the moment, her lightheartedness felt like a strange, comforting gift. It wasn't that this beautiful, dangerous Blade form diminished the Nia he knew. It simply unveiled another facet of her, one that whispered of the battles she’d faced, the strength she’d forged.  There was an honesty in this – perhaps one as important as the secrets they would both still carry.

An odd desire welled up inside Shirou – an itch to do more than just observe. "May I… " he hesitated, looking from Nia to the shimmering weapon in her grasp. "Would it be alright… if I, well… held it?"

The request seemed to catch Nia off-guard. "The sword? Are you serious? Do you even know how to handle a…" She swallowed, the usual flippancy slipping as the reality of her Blade form settled on her again.  He knew he wasn't asking as a swordsman; his touch carried other intentions.

Yet, that hesitation gave way to a slow nod. "I suppose…" A flicker of the old trust was back in her expression. After all, they were past the worst of their secrets, weren't they? “It’s not going to bite, you know," she added, a touch of warmth to offset the worry.

With slow, almost reverent movement, Nia transferred the weapon to his outstretched hands. As the hilt settled in his grip, a shiver shot through him – not a shock, but something far more subtle. The feeling flowed deeper than mere temperature or texture.  If holding another Blade's weapon granted even the remotest sense of their essence...well, he couldn't deny the analytical part of him was now fully engaged. This was an opportunity unlike any other.

"Truly extraordinary," he murmured half to himself, the words a sincere blend of awe and clinical detachment. The weight distribution was immaculate, every line purposeful. Its strange form was deceptive, housing power far beyond what its form seemed capable of.

The sword thrummed, a deep purr beneath his fingertips.  The sensation vibrated, and images flashed across his mind's eye  – fleeting, disjointed snippets not of memory, but of potential. The nature of light, the flow of Ether, the way they twisted and flowed within... It was like reading a blueprint he didn't quite understand, yet grasped intuitively.

Nia let out a soft squeak. "Shirou!" Her cheeks glowed even brighter. "Honestly, stop staring at me like that… at it like that!  My form and all, it's-," she sputtered, "- It's like you're undressing me in your head! Just how long are you going to keep my sword, anyway?"

The understanding he'd gleaned from simply holding Nia's weapon still pulsed fresh in his mind. Not a change to the weapon's core structure – that bordered on Blade creation or modification, far outside his abilities. Yet... what about reinforcement? It was his bread and butter, after all.

"If…if you don't mind," Shirou started, an edge of uncertainty in his voice, "might I have it again, just for a few more moments?"

A curious tilt of the head was Nia's reply. But with a flicker of trust,  the greatsword was back in his hands. That thrumming sensation was stronger now, like a distant heartbeat resonating into his own body. His focus narrowed, an internal mantra playing like the echo of steel on iron: *Analyze. Reinforce. Strengthen.*

"Trace...On," the old spell slipped from his lips almost reflexively. Shirou didn't bother suppressing the blue glow that enveloped his eyes this time. The sword in his hands was an ethereal puzzle – not mere metal and crystal, but a strange living form that pulsed with Nia's very essence. His mind hummed as he mapped out unseen, impossible structures.

From Nia's perspective, the sensation was far more than a simple shiver.  Each mental prod Shirou made felt like a feather-light touch tracing against her very being - strange, a little tingly, and surprisingly not...unpleasant.

Shirou gasped as his vision snapped into focus. It was like seeing an x-ray image superimposed over the sword. Tiny fractures in the etheric structure became glaringly obvious, microscopic fault lines invisible to the naked eye. With his power, his magecraft, those weren't just flaws to be analyzed...they were the key.

Green traced lines flowed from his fingers, the magical energy coiling around the blade with an eagerness it usually lacked. They wove in and around the sword, seeking those minute imperfections. This wasn't his usual reinforcement, not simply wrapping something in power. He was trying to fill the spaces where the weapon itself wasn't whole, to patch those unseen flaws.

It felt...intimate.  Nia let out a soft, surprised sound as the foreign energy tickled her, not unpleasantly. Like tiny currents that surged through the sword, echoed as something warmer, deeper inside of her. The sensations built steadily,  her blush deepening from mere embarrassment to something warmer. Had it always felt this... nice when Rex held her in Driver form? Perhaps those stories of Blade and Driver compatibility weren't entirely made up...

And in Shirou's mind, it all began to click. The flow of power…not just around, but in, becoming part of the sword's structure. There was a logic to it here that even with all the fantastical weapons he'd traced over the years,  felt alien and exhilarating all at once.

Shirou's mind raced faster than his hands could match. The energy flowed eagerly enough, weaving those delicate traceries to mend the unseen flaws, yet...something in that intricate symphony didn't resonate.  It was like playing a beautiful note… just slightly off-key.  He focused again, pushing even harder…

Then came the pushback. Not sharp, violent rejection, but a firm resistance, like a door nudging itself closed after you mistakenly thought it was open. The beautiful thrum of the sword was laced with a dissonance now, a flicker of discomfort that wasn't there before.

With a jolt, Nia straightened her spine, the blush burning across her skin. "Oi, seriously Shirou!" she sputtered. "It feels good, yeah, but… it's starting to get really weird! Can you maybe hurry it up or figure out why…why…" It was hard to get the words out, a strange breathlessness mixing with mounting embarrassment.

Shirou's head whipped up, the traces of green magic vanishing. Confusion warred with dawning understanding.  As much as the idea strained his own understanding, Nia the Blade and Nia the girl weren't separate entities. He'd been looking at this entirely wrong! The connection wasn't the sword as a tool, but as an extension of her own body. If he needed to strengthen that form, to reinforce those barely-there weaknesses, perhaps …

"Um, Nia," he started, trying to avoid the scarlet hue he was sure mirrored her own, "There's…something else I might try. But, well…" This was definitely uncharted territory for his magecraft.  "Think of it like I'm trying to patch a frayed thread. If I want to fix that one spot, I may need to hold and strengthen the whole cloth around it, not just the weakened area directly…"

And that, for all his clumsy explanation, probably didn't make a stitch of sense to Nia.  He hesitated, eyes meeting hers, and then said with a frankness he himself barely recognized, "It means I might have to…well, touch your back, or shoulders. To reach out not toward the sword, but through it, into you." He winced internally. Now it really sounded creepy.

Nia went even redder, if that was possible. "Through me…touch my back?" She squeaked, the words pitched far higher than her usual tone. Then, just when Shirou could almost swear he could feel the heat radiate off her, she seemed to gather herself.

"Fine," she practically yelled, squeezing her eyes shut in a valiant attempt to banish the crimson rising to her hairline, "But I swear, Shirou, the moment any of this feels wrong – the very moment! – I'll jump backwards faster than you can blink!" The last words were more like a panicked squeak, but there was a steel edge to them. An undeniable challenge, despite the flush.  Nia wasn't a girl to be underestimated, and in this particular vulnerability, he couldn't fault her wariness in the slightest.

Nia shifted awkwardly, but with determination, she turned slightly.  With a soft rustle of fabric, she exposed a smooth expanse of shoulder and back towards Shirou, settling cross-legged in front of him. Her skin glowed in the dim light, and  there was a subtle tremble that betrayed her nerves.

Hesitantly, Shirou reached out. This wasn't the first time his magecraft involved skin-to-skin contact, but those fleeting seconds in the heat of battle had been worlds apart from this strange intimacy. His palms hovered just above her bare shoulders for a heartbeat, feeling the warmth radiate from her, before finally settling with a gentleness that bordered on reverence.

As the words "Trace On" hummed from his lips, and that familiar blue glow suffused his vision, an expansion of understanding opened within him. No longer simply an ethereal weapon held in another's grasp, now the blueprints of Nia's Blade form began to overlay not just the sword, but her whole being. It was breathtaking and bewildering at once.

Nia gave a startled gasp, then a tiny half-whimper, half-sigh escaped her.  An electric current seemed to run under his hands, not like his magic, but a ripple of pure sensation echoing in her Blade form. "Oh. Oh wow…" she breathed, the words lost in a shuddering sigh, "That's…"  It was as if a master masseuse was kneading away tension she wasn't even aware she carried.

But for Shirou, this was no mere physical sensation. It was an unraveling of her physical essence, the way ether swirled with something even more primal to create her very existence.  There was a strange kind of beauty in it. Not just the overt attractiveness of her Blade form, but something deeper – a glimpse into  the impossibly intricate workings of this half-formed life. He traced the flow of power radiating from her core, its warmth filling him not with heat, but with a surge of determination. Every pulse of her essence became a new data point, measurements taken not with a ruler but with his very soul.

And so, his strengthening began. Green traces of energy snaked from his palms, not over, but into the living weapon that was Nia herself. No longer simply patching fractures in an impossible artifact, his own power thrummed with a different rhythm, as if the song he sang found its harmony within her Blade existence.

To Nia, it wasn't just bliss; it surpassed everything she'd imagined. Every touch was like a tiny explosion of warmth, not painful, but a slow build of something intense that radiated not just under his fingertips, but seemingly from some place deep within her.   A strange sound escaped her throat, a surprised, purring meow more feline than human, and utterly unlike anything either of them had heard her make before.

But while Nia was lost in sensation, Shirou's mind raced. With a depth of understanding he wouldn't have believed possible, he reinforced, mended, strengthened. It was the culmination of everything he'd been, an analytical mind given a fantastical subject unlike any weapon he’d ever analyzed before. It was breathtaking, exhilarating… and it made him blush furiously. Because for all his focus, there was no escaping the reality of those measurements, and just how perfectly every curve and sinew was laid bare before him. He was learning details even Nia might not be aware of… and perhaps he ought to stop his thoughts there.

Shirou's concentration deepened, fueled in equal parts by a desire to succeed and a rising flush of self-consciousness. Thankfully, this particular blend seemed to sharpen his mental blade even further.  As the green traceries flowed with ever-increasing intricacy, a rhythm emerged – not so much of pressure points, but… well, it seemed remarkably similar to how he might knead stress knots when working on a particularly battered sword.

Of course, this wasn't some metal that simply grew supple under his touch – this was Nia, who vibrated under his fingertips not with rigidity, but a warm hum of something primal. With each circuitous touch, each kneading motion against her smooth skin, it wasn't just magical energy being coaxed deeper, but...well, there was no avoiding that what had started as reinforcement slowly shifted into something suspiciously similar to a massage. Albeit the most bizarre, etheric-infused massage this world had ever known.

He could only hope the rhythmic purrs echoing from under his hands were signs of success, and not...something else entirely.  Yet, despite how awkward things had become, it wasn't without results. With every circuit, her core seemed to resonate a bit stronger, as if those tight bands of power holding her together, which previously only he could see, were gradually uncoiling. Shirou had to force himself to stay in craftsman mode, lest his thoughts slip too far off-task. This was maintenance, like meticulously removing invisible hairline cracks before they could spread. This was… definitely not about feeling those smooth curves under his fingertips, or the surprisingly soothing noises Nia was making...

For Nia, meanwhile, everything had gone blissfully, meltingly wrong. Every inch of her was alight with sensation, tingling and warm to a degree that left her cheeks glowing a furious red. This…this didn't quite match the tingly bits when Rex held her in Driver form. Maybe a more extreme version, multiplied tenfold – and did some part of her actually *enjoy* that? Even just thinking it sent a blush down to her toes.

Yet, even in the fog of pure feeling, it wasn't lost on her just how skilled Shirou was being. It was like magic hands were untangling strands of power inside her she'd never even felt before. Pathways of possibility unfurled with every circuit, with every purr – honestly, if the strange noises didn't stop now, she was going to die of embarrassment – and those pathways whispered of more power, more strength than she'd ever known. Perhaps the utter mortification would somehow be worth it in the end.  But for now, the only thought left in her half-melted brain was a helpless, pleading 'just a bit more...'

The energy pulsed under Shirou's touch, not in a frantic burst, but like a tide drawing back to reveal hidden riches. With each careful touch, he realized, it wasn't just ether he was coaxing to the surface – there was a physical component as well. Knots that weren't of her essence, but simple muscle tension, melted under his hands. Shirou wasn't sure if it was a quirk of her Blade form, or the result of carrying herself too tightly in battle. Either way, he found himself instinctively working the aches out of her back and shoulders, easing them  alongside the magical reinforcement.  There was a practicality to it in his mind, like working the oil into a blade – her own natural flow wouldn't be hindered if her physique was relaxed.

To Nia, though, his hands were spells of wonder.  If there was magic to his craft before, the added physicality unlocked something primal within her. Her mind was barely capable of holding coherent thoughts, only a series of startled 'oh!' and tiny whimpering meows. Each pass of his hands wasn't just easing stress, it was awakening new tendrils of sensation. They coiled low in her belly, tightening and coiling with a slow, steady build that made her cheeks feel set ablaze. This touch, it was…

Warmth flooded her like she'd never known. There had been comfort in Rex's presence, the security of a Driver and Blade bond, a camaraderie born of hardship and mutual purpose. This, though, this was on a different level entirely. Her body seemed to realize it before her mind did – warmth spiraling into pleasure, and suddenly her thighs were pressed together as a desperate gasp threatened to slip past her lips. There was no mistaking what this was anymore, no mistaking how her Blade body trembled and writhed under his well-intentioned touch. Pure, unadulterated, girl-sized embarrassment surged alongside the other feelings. Mortification battled with an unwilling plea that resonated far, far deeper – please, oh gods, don't let this stop...

But Shirou remained utterly oblivious. In his craftsman's mind, the process wasn't complete.  The flow from her core hummed beneath his hands, stronger with each pass. Yet, there were those delicate spots around her shoulders, like misaligned joints in a masterwork weapon. If his reinforcement held true, it was there that the truest potential lay. With a renewed focus, he concentrated the flow of his magical energies, the green traceries flickering to a gentle blue at the tips. Each careful pass was like polishing away imperfections in a priceless blade, seeking that moment of pure resonance where form and function sang in flawless harmony.

Shirou's understanding wasn't simply theoretical anymore. As his magical sight unraveled Nia's blueprint, a different form of intuition kicked in – not simply an analysis of structure, but an instinctive attunement to this body that transcended inanimate material. It was less like he was polishing a weapon, and more like a musician who learned a beloved instrument; each curve resonated with purpose, every swelling an amplification of the power held within. With startling clarity, he visualized how ethereal energy swirled, snagging where it shouldn't in unforeseen imperfections, and where it desperately yearned to flow unhindered.

For a sword, this realization would mean fine-tuning the balance, reshaping the hilt for perfect purchase. With Nia, the implications sent an unexpected flush to his face. Optimal reinforcement didn't simply call for magical expertise, but his touch, his hands on her hips, guiding the flows. His fingers would have to slide along  her thighs, where  points pulsed with receptive warmth even beyond his magical sight. This wasn't about analyzing – it was about wielding her in a way he hadn't foreseen, the kind of understanding that would make Rex turn crimson if he found out.  Shirou opened his mouth, uncertain how to even begin to explain what he was seeing, feeling...

Nia cut him off. The lack of his touch when he hesitated was agony, the warmth fading into a desperate craving. The word escaped as a raw plea, her voice barely recognizable as she shifted closer, pressing against his back with a need she barely understood. A low, desperate hum filled the space between them, almost more feline than human.  She hadn't felt alive this way in what felt like forever. As a Blade, the sharp edges of human need had been softened, a sacrifice willingly made.  Yet now, under Shirou's hands, those embers roared with an intensity she never expected. This wasn't merely nice, wasn't just pleasurable... it was an awakening.  The sword in her core seemed to thrum in sympathy, as if her entire being had become a receptive node to his touch.

There was no point to analysis now, no craftsman's explanation.  She wasn't sure she would be able to string a proper sentence together if she tried. The plea vibrated from her lips, an instinctual surrender more than a spoken thought: "Just a little more… please. Wield me…"

This wasn't about reinforcement anymore. It was about touch and fire, the desperate desire to feel...to feel more of…everything. With those breathless words, Nia wasn't simply baring her back to Shirou. She was laying herself open in a way she'd never imagined for anyone, offering her Blade form and everything it implied for him to explore, exploit, or perhaps... embrace.

The moment his hands settled on Nia's warm thighs, Shirou couldn't pretend ignorance any longer. It wasn't the analytical part of him that reacted to her involuntary whimper, the way she arched almost desperately into his hold. That instinctive understanding of where to press, where those receptive energy nodes lay – those weren't mere blueprints now. Shirou, with a bone-deep awareness no teenage boy should have, registered just how ready she was for this touch, this…more.

Her past echoed in him – the driver who'd given her that monstrous order, the way she'd molded around a different wielder's needs. Even with everything they shared, Shirou knew Nia shouldn't have to fight to understand her own desires in his company. His wasn't the touch of a Driver, he had no command over her in that fundamental sense. There was choice here. No, more than choice – Nia was all but flinging that decision into his hands, blind with need and desperate trust. Shirou had known power's terrible cost, that rush when lines between right and wrong were blurred for his own desires. But to wield it against that vulnerability... he wasn't Kiritsugu. And maybe, just maybe, Nia deserved...more.

It was with unexpected gentleness that he moved, fingers feather-light until he located that key point on her inner thigh. No longer searching for flaws, but the conduit for an unhindered flow. She gasped when he traced a line towards her hips, not out of pain, but in sharp contrast to the desperate anticipation vibrating through her body. Each movement felt intimate, each spot he held with lingering warmth was a revelation of her response. She spread her legs further, and a tiny broken noise tore from her throat. Heat filled the air in a palpable wave, mirroring his own rising blush.

Even while a part of her mind desperately tried to rationalize what was transpiring, Nia realized this wasn't…not simply how Blades felt when Drivers held their weapons. This was deeper, the intensity sharper, something primal clawing at her from within. She couldn't help but wonder how they ended up at this point, the two of them in this dimly lit room, acting more like some heated lovers than comrades caught in a fight for their lives. And even that word 'acting' barely fit.

But with another touch, with another surge of power filling her form, her thoughts vanished. "Trace On," echoed Shirou's voice, a lifeline amidst the swirling sensations. Green lines traced along her skin, vibrant against the backdrop of her soft form, weaving their intricate spells throughout her being. Shirou wasn't merely bolstering her sword now, he was reinforcing her in the truest sense – every line like a caress that resonated far deeper than skin. His touch, unlike those of previous Drivers, felt as if it had no barrier to bypass, reaching into the very core of where Blade met human. This, somehow, filled the gaps Rex could never reach.

With every circuit,  the sensations amplified. This wasn't simple pleasure now – this was completion, something echoing from a primal place hidden even from herself. If his hands were magic before, now they were flames setting her on fire. As climax hit, it wasn't simply physical; it was the sword and the human in unison, every inch of her form thrumming with blissful heat and satisfaction.  Her moan ripped through the air, an utterly undignified sound,  followed by a name torn from her heart: "Shirou…" This wasn't the cry of a Blade to her Driver, but of a girl finally feeling... whole.

And while a part of her, a tiny speck of sanity, wanted to die right there in that explosion of feeling, her heart surged with more than embarrassment.  There was… something else there, the whisper of something that scared and thrilled her equally.

The aftermath hung heavy between them, an invisible storm churning amidst the fading traces of magic. Shirou's hands still ached with the phantom sensation of every curve and swell – an imprint of a woman laid bare in a way he never earned the right to know. This hadn't been a simple reinforcement. His touch wasn't merely a craftsman honing an instrument, but a sculptor leaving permanent marks on the marble of her being. Watching his magecraft cascade through her, he'd glimpsed a vulnerability beyond what swords and battles exposed. Now, the very air pulsed with an energy more dangerous than any battlefield, a lingering heat that spoke of unlocked secrets and echoes of those waves of sensation that he had no right to feel.

And still, amidst the chaos, something protective sparked within him. He’d violated her trust, no matter how unwittingly, and platitudes wouldn't patch that wound. It demanded acknowledgment, respect… something even his magecraft couldn't undo. All of that unlocked power wasn't a shield. It was her body's instinctive rejection of shame, a primal awakening demanding not a craftsman's touch, but…an answer.

Unfortunately, Nia wasn't making things easy. There was shame still, in the self-defensive curl of her posture, the desperately averted gaze.  Her mumble felt like a wounded animal retreating into its den:  "That was…unfair. Never...gods, ever, with any other…” It wasn't about feeling good, not anymore. What hung heavy in the unspoken words was the echo of 'felt so deeply as a woman'. She'd gone to a place so utterly personal that, no matter how well-intentioned, no magic could undo that. There was an awareness on her flushed face, a shift she might not quite grasp, and the echoes of what had been unleashed now threatened to drown her in unanswerable questions.

He saw it all unfold within her, the mortification and wonder warring for dominance.  Nia buried her face in her hands, and an unexpected low whine followed, a raw ache buried in the warmth lingering like a blush across her skin.  As it faded, she drew a shuddering breath, and there it was – a single tear streaking down her cheek. Her world was tilted, irrevocably marked by an intensity so unfamiliar it bordered on terrifying. Shirou wanted more than anything to make it easier for her, but as his hand hovered inches from her shoulder, something stayed it. Words hung like dust in the air, apologies choking back any pretense at ease. It was his touch that caused those unbidden sounds, unleashed this potent awakening of woman and Blade. His craft might have brought change, but he couldn't wield it again to reverse the tides, not after he’d ripped away the safe boundaries between them.  The power still coursed through her, demanding the answers he wasn't qualified to give.

"This, uh…" Shirou felt the utter inadequacy of his words, but her muffled sobs demanded that he pierce the silence with…something.  There was no hiding what his magecraft had wrought. "The reinforcement...it amplified everything. But it went beyond the weapon form, didn't it? My...craft doesn't just change a sword, it shapes what makes the whole. This was something in there already, and I, well, I…"  How to apologize when words only seemed to make it worse?  He longed to explain, to analyze, but there was no explanation for the depth of impact, for how deeply he felt its echoes within himself. It was too messy, too human, and far, far beyond his expertise. So, Shirou settled on the only honest choice left, the desperation raw in his voice, "How do you feel….truly? Don't try to hide it, please, Nia. Tell me how this has shaken you. It wasn't your Blade form I altered, it was…" But what words could encompass this tangle? Of shame, of awe, of the sudden weight of responsibility he hadn't even fully understood until he witnessed her tears?

Silence filled the space, but for Nia, it wasn't heavy. It crackled with the residual aftershocks of what had transpired.  She shifted, and a low giggle escaped past her lips. "Honestly, Shirou, is there a part of my form your magecraft doesn't understand by now?" She batted her lashes at him, the mock scolding in her tone softened by a lingering breathlessness. "Seriously, what were you thinking, doing something like that? Don't try to blame this on whatever toolkits and instruction manuals they give you back home," she continued, "Because there's no way you were this clueless without it being on purpose!"

Under his gaze, she couldn't quite meet his eyes. But a flush was evident on her cheeks, and a certain swaying of her hips hinted at a kind of restless energy she seemed unable to contain. She couldn't stifle the next breathless admission, words that felt both bold and incredibly reckless. "It was…amazing. Beyond even what I…well…" Heat burned brighter with each word. "That wasn't just some 'power-up', Shirou," she muttered, barely more than a whisper. "This changes things. And it felt unbelievably good." Her voice hitched then, catching on those last words – a mix of defiance and something deeper, something a tad needy that even she was still processing.

With a surge of honesty, she confessed, "The sword felt incredible – sharp as anything you've ever held, I imagine. Like I could move mountains without breaking a sweat! But my senses… my whole body…it's like…” her hands danced in front of her, unable to truly capture the sensation. "I feel… alive, in a way I haven't ever felt before! All overcharged and jittery with power!" The energy coursing through her was impossible to deny; it vibrated in every touch, every tiny shift of her weight.  Suddenly, a grin played at the corner of her lips, "Honestly, I’m surprised there aren't sparks flying off me!"

A thought tickled the edges of her excitement, and she couldn't resist poking at it. "Hey," she leaned conspiratorially close, "You always get that intense craftsman look during battle. Was it always this…" her voice dropped to a teasing whisper, "fascinating…working on me?"  There was a playful tease in her voice, but within it lurked a more serious current. Perhaps… maybe this intensity and connection they'd just forged wasn't so unwanted after all. This newfound physical awareness hummed a thrilling chord inside her. This wasn't how Blades usually felt, she was certain of it now. She'd felt good enough during battles, but now it was like the dial had been turned to a hundred. Shirou hadn't just strengthened her as a weapon; he'd stirred an echo of something else, something personal and intoxicating. Whether or not either of them was prepared for that – whether she even fully grasped what it might mean – well, that was a question for later. Right now, the rush, the raw buzz of possibility, and maybe that hint of defiance in the face of their strange situation…it was more exhilarating than any fear or uncertainty. This, she decided, was the perfect time to test out this newfound vitality.

The air hung heavy with Shirou's silence, a stark contrast to Nia's vibrant energy. Even in the dim light, he couldn’t hide the crimson creeping over his face. Making people smile? Sure, a bit of relief in the darkness of their current battles, that was something he understood. He'd even found purpose in the simple act of fixing that darn coffee machine. But this…this explosive spark he’d ignited in Nia wasn't simple joy. This was the kind of heat that melted swords, left the craftsman breathless, and sent his well-meaning intentions up in flames of unintentional intimacy. It wasn't relief that surged through him now, but a heady concoction of guilt, awe, and the lingering ghost-sensation of her skin moving under his hands.

It was Nia who brought the silence back to something…well, it felt wrong to call it normalcy. "So…" she drawled, stretching with exaggerated languor, a feline hint to her motion, "Just making me smile, was it? Don't get me wrong, that's usually appreciated, but you went a bit, shall we say, above and beyond this time."  There was a glimmer in her eye, as much challenge as playfulness. His own heart felt like it leaped at the proximity, the ease with which she moved like a cat finding its spot on the blankets. Shirou wasn't sure if retreating would make things better or worse. Instead, he found himself trying to retreat into the comfort of logic, as flimsy a shield as it felt right now.

"The-the touch," he managed, forcing the words out in a tone far calmer than he actually felt. "It gave me an understanding of you. While tracing, I'm… it's more than analyzing an inanimate object. I visualize...blueprints." Shirou desperately hoped that didn't sound as crazy as it felt. "With this, it was every line, every energy node. Each curve… it helped me see the bigger picture, how to really reinforce." The blush intensified with each awkward word, the truth echoing between them. He'd understood everything – her strength, her potential, and something far more intimate than any weapon analysis should entail.  "

And, well, maybe…" he began, the words hesitant but spurred on by an instinct stronger than his embarrassment, "Blades...you weren't designed to feel reproduction the way...well, people do... but with how everything else functions so perfectly…" The explanation hung in the air, unspoken but clear. This wasn't her malfunctioning – maybe something far stranger had ignited. Could a being so meticulously crafted to fulfill a warrior's role also encompass this depth of physical sensation? It was a question too far out of his usual understanding, yet impossible to ignore in the face of Nia's raw vitality.

Speaking of which, as Shirou finally met her gaze, he realized just how close she had gotten.  She’d shifted onto the bed, now straddling him with the confidence of a conqueror. He knew how strong she was, and suddenly, he felt shockingly fragile beneath her.  There was a feline quality to how she perched, an undeniable possessiveness in her playful grin. “Exposition at a time like this?" she breathed, the hint of laughter bubbling. Her voice lowered, husky with a mix of warmth and mischief, "It makes it all the worse, you know…that I suddenly have all this pent-up energy this late at night…" Nia leaned down, a tantalizing strand of hair falling over his cheek. Whether it was to close the distance between them, or just to torment him, Shirou had no idea. His own heartbeat thrummed in his ears, the magecraft coursing within him feeling a lot less controlled than a few moments ago.

Shirou recognized the shift in Nia, the raw energy echoing within him. He knew his actions hadn't just strengthened her, they'd awakened something profound. With all his knowledge, and her uncanny resemblance to a woman's body, perhaps her latent humanity… the womanhood woven into her form…was now undeniable. His touch might have been the key, but this fire was all her own.

"It's because of how I look," Nia murmured, realization replacing earlier confusion. "But, there's no…manual for Blades, is there?" She was searching for understanding now, and an undeniable hunger fueled the blush warming her skin. Her voice softened, "You didn't do anything wrong, Shirou. I…did I do something wrong by liking how you made me feel?"

A deep breath settled Shirou. He wouldn't retreat from this. She might be a Blade unlike any he'd known, but the question ringing between them held a vulnerability too human to ignore. "If it felt good, Nia…that's not wrong. Perhaps you weren't meant to feel this way when you were created… but if your body can," he looked at her earnestly, "and it sounds like it very much can... I think that's okay." It was a terrifying admission – of how deeply his innocent act of reinforcement had shaken her, and also his own unexpected response. "It was me, but... the fire was always there within you. Now, it's up to you how you…let it burn."

Nia leaned in, the spark in her eyes now blazing with a different kind of power. "So… you take responsibility," she mused, voice hinting at mischief mixed with something raw and untamed. "You say this new awareness is yours to shape… but it feels dangerous, too big to handle alone." A delicate caress traced his jawline, and her words lowered to a near-whisper, "You woke me up, Shirou. Show me this world you've opened."  It was a plea, disguised as a dare. Could he teach her a pleasure her creators had never foreseen?

More than that, a challenge hummed in her touch – was he willing to navigate the consequences of what he'd unleashed? His craft had gone beyond blades and swords now; he'd stumbled onto something delicate, frightening, and far too complex for any simple explanation. Yet, how could he deny her? After everything, could he refuse this plea for knowledge when her world had changed so rapidly beneath his fingertips? Perhaps this was the responsibility he never asked for, a duty carved on her newly receptive flesh and his now-trembling hands. His answer was simple, mirroring the stark honesty in her eyes: "Yes."

This night wouldn't be easy. He was unprepared for the depth of his actions, for this wildness now blazing in Nia's gaze.  It would be a learning experience of a nature far beyond any spell-craft, the messy navigation of emotions, of pleasure woven with something more fundamental to her being.  But if Nia was as willing, as curious, as aching for answers as he suspected…this new path, forged in the heat of unintentional intimacy, wouldn't be one they walked alone.

Hours blurred in a heady blend of discovery and intimacy. Shirou had been a craftsman, an explorer, and somewhere amidst the wild dance of touch and response, something more ignited between them. It felt both reckless and inevitable, and by the time they fell into exhausted, sated sleep, he'd lost count of who led and who followed in the symphony of sensation. They'd mapped out secrets on skin, navigated unspoken questions with trembling hands. There was a kind of tenderness that surprised him, nestled among the fiery awakening she'd so bravely sought.

Morning came far too soon, sunlight filtering through the curtains with a harshness at odds with the lingering warmth between them. Shirou stirred first, the weight of Nia's head on his chest a comforting, and frankly rather complicated, reality to reckon with. Her body nestled against his, the outline of her Blade form imprinted not just in his mind, but with a bone-deep familiarity he wasn't ready to unpack.  His thoughts threatened to turn analytical—that curve, the precise flow of energy within her now... He shut that down with a force that had him wincing. Not now. Not with her sleep-softened face framed against his shoulder. There was a peace in her expression he yearned to protect, even if it felt fleeting in face of what a simple knock on the door might herald.

With gentle nudges, a whisper of apology against her hair, he attempted to untangle himself from their impromptu bed. To his utter relief, Nia remained fast asleep as he carefully slid free, a warmth resonating through him despite the chill of the room. But as he reached for his hastily discarded shirt, her eyelids fluttered open.

There was a moment of disorientation, then a feline stretch that made his breath hitch. She yawned, the sound muffled and adorable, but it couldn't erase the faint flush on her cheeks as she blinked owlishly up at him. "Mm.. mornin'..." her words slurred and sleep-rough, punctuated by a yawn that bared tiny glimpses of teeth. Nia, then, with a hint of that feline sensuality from hours before, but layered with a casualness that nearly fooled him into thinking last night had been anything close to usual.

Then, her eyes widened. Memory seemed to crash into her not unlike a bucket of ice-cold water. The blush wasn't the soft color of dawn now, but a fiery hue spreading across her skin. With a startled shriek that could probably wake the entire neighborhood, she leaped off the bed, fumbling for a blanket with frantic speed.  "You! I! It can't be…what were we…last night…was…oh gods!" Her stammering was so unlike the warrior's confidence, it drew a shaky laugh from Shirou.

Despite the sudden shift, Nia was Nia. Even as she morphed into an incandescent tomato, covering as much of herself as possible in record speed, there was a hint of defiance in the way she met his gaze. The embers of what they'd awoken were still there, even if a hurricane of self-consciousness threatened to douse them.  There was no pretending last night hadn't happened, but he couldn't let it vanish into awkward silence either. With a hesitant step towards her, his tone was an echo of the night's honesty, "We…well, I reinforced you as far as possible…with some unorthodox methods. I might have… gone a bit overboard…"

Nia couldn't hold back a snort despite the burning in her cheeks. "Just a bit overboard, you say?" she echoed, a teasing edge cutting through the embarrassment.  The memory of those intense waves of sensation wasn't fading even a tiny bit, much to her mortification. She fumbled with a button – damn these outfits had more fasteners than a battleship!– the fabric doing little to hide the way her skin seemed to pulse with every stray memory.

Yet, a flicker of boldness surged through her. Underneath that absurd outfit, her Blade body… the part that truly connected with Shirou in those intimate hours…  that part didn't hum with embarrassment. That part thrummed with an intense and undeniable power.  A hint of the defiance she'd shown him after her initial transformation returned with a vengeance. "Well," she quipped, "At least nobody can accuse me of not being at my absolute best in the next battle, no matter how strange your methods might have been…"

Quickly throwing on her disguise, she glanced at Shirou.  For a second,  she considered the usual banter of 'avert your eyes or face my laser sword!'. Yet… it just didn't fit anymore. Not after baring more than just her body, but a vulnerability even fiercer than any monster they'd ever faced.   There was no sense trying to deny what had happened. Still, with hands carefully smoothing the folds of her dress, she added, "If you could perhaps not share the finer points of… last night's maintenance... with the others, well, I'd prefer to put up a brave front just a little longer, yeah?" The plea in her voice wasn't simply about secrets; it was a hope to regain just a smidgen of the control she felt slipping away after every stolen glance at Shirou.

He didn't disappoint. In the face of her half-serious tone, he managed a sheepishly wry grin. "Like you never accidentally walked in on Rex…." the beginning of a tease hung in the air, only to be cut off with a surprisingly earnest expression. "Alright. It stays between us." It was a silent agreement, and one he found unexpectedly… nice. Not even their closest bond with Rex had this layer of secrecy. It was just them now, bound not only by combat and survival, but by an intimate knowledge of each other no one else would ever share.   The thought sent a warmth through him that transcended any embarrassment.

And then, because he simply couldn't resist one last quip, he added, "But hey, just for the record, if this is how you feel from 'overboard' reinforcement…" A wry smile tugged at his lips, "...just… please.  Never ask me to fix anyone else's sword...ever." It was lighthearted, and he hoped to mask just how deeply shaken he was by the entire experience. But somewhere amidst the blush and teasing,  a sliver of his true feeling slipped through – last night hadn't simply been a duty. There had been pleasure in it, and if Nia wanted to explore that again, well, his heart pounded traitorously at the very thought.  Perhaps she didn't want to go back to how things were. Maybe... that was okay.