The lingering mist hanging over the northern ridge didn't smell like rain. It smelled of ozone, burnt pine resin, and the sharp, metallic tang of flash-vaporized copper.
Moments earlier, the search unit had been standing at a complete standstill near the outskirts of the lower artisan district. After finding Kai's office empty—and receiving a supremely unhelpful, dry dismissal from Administrator Siris—Cana had been on the verge of fanning out her divination cards on a tavern barrel to pinpoint his magical signature. But before she could even channel her ethernano through the deck, the ground beneath their boots had shuddered.
It wasn't a natural tremor. It was a rhythmic, violent thudding that rattled the glass in the shopfronts, followed three seconds later by a muffled, booming detonation from the direction of the northern forest.
"North," Juvia had snapped instantly, her eyes narrowing as her internal water-sensation picked up a violent spike in atmospheric humidity and sudden thermal displacement. "A high-density magical release. Kai-sama is there!"
They had moved as a unit—Cana, Mira, and Juvia taking the lead, with Princess Hisui trailing closely behind, guarded by a deeply stressed Captain Arcadios and a full detachment of heavily armored Royal Guards. They broke through the thick treeline expecting to find an ambush, or perhaps a rogue creature from the mountains.
Instead, as the lingering cloud of white steam and dust slowly parted, the clearing before them looked as if a minor war had been waged in complete silence.
The landscape was unrecognizable. Massive, deep trenches carved through the solid bedrock like jagged lightning bolts, smoking with residual heat. Three massive pine trees lay severed in half, their trunks cleanly sheared as if by a giant blade. Craters pockmarked the flattened grass, and scattered everywhere were torn strips of dark cloth, shattered iron fragments, and dark, drying splatter across the earth.
And right in the center of the carnage stood Kai.
His leather coat was gone, resting on a log twenty yards away. His sleeveless black tunic was torn across the chest, exposing a deep, bloody gash, while his forearm wrappings hung in shredded, blood-soaked ribbons. Steam was still lazily venting from his shoulders and chest, his golden eyes half-lidded, his posture slouched as he scratched the back of his ear with a bloody thumb.
Opposite him stood the mysterious swordsman. The stranger was leaning heavily against his left side, his dark hair matted with sweat and dried blood. His face was a bruised mess—a shattered left cheekbone turning purplish-black, blood dried beneath his nostrils, and his right arm hanging completely useless at an unnatural angle from a dislocated wrist. Yet despite the horrific damage and the sharp, shallow breaths betraying his fractured ribs, his left hand still loosely held the silver-hilted blade. His crimson eyes remained cold, calculating, and fixed on Kai, radiating a quiet, lethal pressure that completely belied his broken physical frame.
The reaction from the incoming group was instantaneous.
"On guard!" Arcadios roared, his hand slamming onto his broadsword hilt as the Royal Guards instantly fanned out, their heavy iron shields locking into a defensive wall around Princess Hisui.
Cana's hand blurred, pulling three explosive cards from her deck with a sharp flick of her wrist. Juvia's eyes flared a brilliant, dangerous blue, a spinning water-selection magic circle manifesting directly behind her shoulders with a low, rushing roar.
The air in the clearing turned razor-thin.
Kai looked over his shoulder, blinked at the sudden armed assembly, and let out a long, long-suffering sigh that sounded like a deflating tire.
"Whoa, whoa, whoa," Kai shouted across the torn-up field, waving a limp, blood-stained hand at them in a dismissive circle. "Hold your horses, people. Put the flashy magic away. No need to be so jumpy."
The guards hesitated, their boots freezing in the dirt. Cana slowly lowered her cards, her jaw dropping slightly in absolute bewilderment, while Juvia's magic circle flickered and dissolved into a harmless mist.
"What the hell happened here?!" Cana barked, taking two aggressive steps forward over a severed pine branch. "You said you were just going to meet the guy! Did you try to negotiate by throwing mountains at each other?!"
Kai didn't answer right away. He stretched his neck, his vertebrae popping with a horrifyingly loud crack, before lazily plopping down right onto the grass, crossing his legs with absolute, unbothered comfort. He patted the flattened dirt right beside him and offered a limp gesture toward the girls.
"Can't you guys just talk by coming over here?" Kai called back, his tone thoroughly unimpressed. "I'm really not in the mood for shouting across a field. My throat's dry, and I've got enough fresh ventilation in my chest already."
The entire group stood frozen for three full seconds, staring at him. He looked like a man who had just finished a mild afternoon stroll rather than surviving a localized natural disaster.
Hisui looked at Mira, Mira looked at Cana, and with a collective, bewildered exhale, the group began marching rapidly toward the center of the clearing.
Meanwhile, Kai turned his head toward Rei, who was still standing five feet away, leaning heavily on his left foot with his jaw tight against the blinding pain of his broken ribs. Kai raised a single eyebrow, patting the grass beside his knee.
"Take a seat, dude," Kai muttered softly. "You look like a breeze could knock you over."
Rei didn't move. His crimson eyes flicked down to the grass, then back to Kai's slouched frame. "I prefer standing," the swordsman replied flatly, his voice raspy from the internal trauma to his chest.
Kai let out a low hum, resting his elbows on his knees as he stared up at the sky. "Yeah, fair enough. Sorry, I forgot you have a stick shoved so far up your ass it's practically load-bearing. Better to stay vertical, otherwise it might go even higher."
Rei's brow twitched. He scowled down at Kai, a low, exhausted curse slipping past his lips, but he lacked the spare breath to actually formulate a proper retort. He settled for shifting his weight slightly, keeping his left hand clamped tightly on his silver hilt.
Within moments, the group swarmed the small patch of flattened earth. But as they finally crossed the final threshold of dust and saw the full, horrifying reality of both men's physical conditions, the annoyance and confusion on the girls' faces completely melted away.
Horror and sudden panic took its place.
Rei was instantly written off as a non-entity by the women. The Royal Guards immediately flanked the dark-haired swordsman, their spears levelled at his chest from a safe five-yard distance, treating him like a ticking tactical bomb. But Cana, Mira, Hisui, and Juvia completely ignored the stranger, aggressively crowding around Kai instead.
Up close, the damage was brutal.
A long, jagged cut ran diagonally across Kai's torso, the edges cauterized in some places and seeping fresh crimson in others. His forearms were covered in sharp, bloody lacerations where blade pressure had cut through his spell-bound wrappings. Even his face hadn't been spared—a thin, crimson line ran from his chin, crossed his cheekbone, and disappeared up toward his temple.
Yet, Kai simply sat there, absentmindedly using his pinky finger to scratch the inside of his left ear, looking thoroughly bored as he towered over the kneeling girls.
"Kai..." Mira's usual serene voice cracked slightly. Her gentle blue eyes searched his face, her hands hovering over his shoulders as if terrified that touching him would break something internal. "Are you... are you alright?"
Hisui stepped right into his personal space, her hands clutching the front of her royal dress, her face pale as she looked up at his chin-gash. "Does it hurt? Kai, speak to us! What is all this blood?!"
Juvia was nodding frantically beside her, her hands wringing together so hard her knuckles turned white. "Kai-sama! Please, allow Juvia to summon cooling water to wash the wounds! You are... you are leaking!"
Kai stared down at the three of them, his golden eyes sliding from Hisui's frantic expression to Mira's trembling hands. He let out a slow, deliberate breath, his shoulders rising and falling.
"Well... I feel like a badly peeled potato," Kai said flatly. "Does that answer your question?"
An awkward, heavy silence settled over the circle.
Cana crossed her arms, her eyes darting from the bloody trench behind him to the severed trees, her face a mixture of deep irritation and suppressed panic. "What the hell even happened to you? And to this place?! It looks like a dragon had a seizure!"
Kai gave her a thoroughly unimpressed, deadpan look. "Are your eyes just for decoration, Brownie? Can't you see what happened? Two guys had a difference of opinion, and the scenery suffered for it."
"I am trying to ask why a simple conversation required demolishing a state-protected forest!" Cana snapped back, her cheeks flushing slightly from his dismissive tone.
"Siris explicitly told us you left for an official off-site meeting!" Princess Hisui chimed in, marching right up to his seated frame, her small boots stomping into the dirt. She pouted up at him, her chest heaving with royal indignation. "How does an administrative meeting turn into... this?! And who is this person?!"
She pointed a sharp, delicate finger over her shoulder toward Rei.
Before Kai could answer, Captain Arcadios stepped forward, his heavy iron boots crunching on the gravel. His scarred face was hardened into a deep, authoritative scowl as he glared past Kai, straight at the bloodied swordsman.
"I would also like an answer to that, Director Sunveil," Arcadios rumbled, his hand resting firmly on the pommel of his sword. "This man possesses no official guild emblem, no citizen identification. Yet he has engaged a high-ranking Ministry official in full combat, resulting in severe public property damage. I am within my legal rights to place him under immediate military custody."
Kai tilted his head back, looking up at Rei with a raised eyebrow, as if silently asking: 'Well? You gonna take that, or are you gonna introduce yourself?'
Rei didn't flinch under the gaze of a dozen armed royal knights. He stood tall despite his shattered ribs, his voice cold, calm, and utterly devoid of fear.
"My name is Rei," the swordsman said simply. "I am a traveler. I am not affiliated with any dark guild, nor do I have any intention of harming the citizens of Crocus. I came here solely because I had business with Director Sunveil. You have no reason to concern yourselves with my presence."
Arcadios let out a dark, amused scoff, his grip tightening on his sword. "How can I possibly trust the words of an unregistered wanderer who offers no paper trail, stands in a ruined clearing, and is currently holding a drawn weapon?"
Rei's crimson eyes flicked down to his silver sword, still held loosely in his left hand. "It is drawn for self-defense," Rei said smoothly. "And it will remain passive... provided you do not force my hand."
A visible vein throve on Arcadios's forehead.
The Captain of the Royal Guard didn't draw his blade, but the tension radiating off his body was palpable. Arcadios was no fool. He could feel the sheer, suffocating pressure lingering around this 'Rei.' The man was broken, bleeding, and using his off-hand, yet the lethal intent radiating from him was unmistakable. Furthermore, the stranger had gone toe-to-toe with Sunveil—a man Arcadios knew for a fact could dismantle an entire platoon of heavily armored royal knights without breaking a sweat.
Seeing the dick-measuring contest spiraling out of control, Kai let out another loud sigh.
He pushed himself up off the grass, his joints clicking loudly as he stepped directly into the line of sight between Arcadios and Rei, holding out both hands in a classic 'calm down' gesture.
"Alright, alright, stop with the stare-down of ultimate domination," Kai drawled, stepping casually into the crossfire. "Put the pointy things away, children."
He turned to Rei first. The swordsman held Kai's gaze for a second, saw the completely unbothered, dangerous glint in those golden eyes, and quietly slid his silver blade back into its scabbard with a soft, metallic click.
Kai smirked, turning back to face Arcadios. "See, Captain Hook? He's a sweet guy. Completely harmless." Kai leaned in slightly, his smirk widening into something razor-sharp and terrifyingly playful. "Besides... if he actually wanted to do something bad, you and your boys wouldn't be able to stop him anyway. But luckily for you, you've got your handsome, extremely talented Director right here. If he tries anything funny..."
Kai paused, tapping his own chest with a bloody thumb, his smile remaining completely warm and cheerful. "...I can just kill him. And he probably knows that."
The entire clearing went dead silent.
The casual, lighthearted way Kai delivered a blatant threat of execution—paired with the fact that Rei didn't even argue, merely offering a faint, blood-spattered smirk of agreement—made the temperature in the forest drop by ten degrees. Even Arcadios felt a cold drop of sweat slide down the back of his neck.
Hisui broke the silence, clapping her hands together sharply to break the eerie atmosphere.
"That is quite enough!" Hisui declared, stepping past Arcadios and glaring up at Kai. "Captain, order the knights to stand down immediately. Director Sunveil is bleeding through his clothes, and he needs to be taken to the royal physicians at once!"
Kai looked down at his chest, as if only just noticing the dark red stain spreading across his tunic. "Oh, yeah. Look at that. I am bleeding a lot."
Without waiting for the physicians, Kai casually reached his hand into his small, enchanted leather hip pouch.
He rummaged around inside for a few seconds. Metallic clinks echoed from the tiny bag, followed by the faint sound of turning gears. A second later, a small, silver-plated mechanical spider—no larger than a teacup—poked its head out of the pouch opening. It held a dark, wooden flute in its tiny, brass mandibles.
"Good job, Pixie," Kai hummed smoothly.
The little mechanical spider gave a soft, rhythmic click-click-click with its legs and vanished back into the pocket dimension.
Kai held the flute in his hand for a second.
The moment the instrument cleared his pouch, a strange, heavy static filled the air. Hisui, Arcadios, Juvia, and even Rei instantly felt a subtle prickle along the back of their necks—a faint, ancient residue of dark ethernano that made their instincts scream. It felt wrong, heavy, and unnatural.
Before anyone could ask what it was, Kai casually tossed the dark flute across the clearing.
"Here, Clouds. Catch."
Mirajane's hand shot out on instinct, snatching the dark wood cleanly out of the air. She looked down at the instrument in her palm, and a sudden wave of absolute relief and gentle amusement washed over her features.
"Oh," Mira sighed softly, her bright smile returning in full force. "Of course. How could I forget? You still have Lullaby."
Kai shrugged, rolling his damaged shoulders. "Probably because your brain is tiny, Clouds."
Meanwhile, Hisui, Arcadios, Juvia, and Rei were all staring at the dark flute in absolute horror.
"Lullaby?!" Hisui gasped, her eyes wide as saucers as she backed away a step. "The... the demon mass-murder flute from the dark guilds?! The song of death?!"
Arcadios drew his sword halfway out of its sheath in sheer panic. "Director Sunveil! What is the meaning of this?! That is a high-threat level dark artifact!"
Kai waved his hand dismissively, thoroughly annoyed by the screaming. "Relax, calm your brass buttons. Yeah, it used to be a dark magic artifact. But I completely overhauled its internal runic matrix. I stripped out the soul-eating resonance, inverted the acoustic ethernano conversion, and repurposed the structural frequency. It doesn't kill people anymore."
Hisui, Arcadios, and Rei stared at him as if he had just claimed he re-engineered the moon.
"You... you remade a Zeref construct?!" Rei whispered, his stoic facade cracking in genuine, profound shock. "You altered the fundamental logic of a cursed demon mass-murder weapon?"
"It wasn't as easy as it sounds," Kai said deadpan. He turned his eyes back to Mira. "Anyway, Clouds, give it a blow. If I try to play it right now, my terrible technique combined with these extra punctures in my chest means I'll probably just spray blood all over the grass."
Mira giggled softly, a sweet, dark aura momentarily floating around her. "I could always just let you bleed a little more for calling my brain small, you know."
"Do it, and I'll swap your shampoo with blue hair dye again," Kai warned with a lazy smirk.
Mira sighed, placing the dark wooden mouthpiece to her lips.
She took a soft, steady breath and began to play.
A slow, hauntingly beautiful melody washed over the ruined clearing. The music wasn't dark or oppressive—it felt like a gentle spring breeze floating over cool water. The heavy, suffocating atmosphere vanished instantly, replaced by a deep, soothing warmth that settled directly into their bones.
As the notes drifted through the air, something miraculous happened.
The deep, bloody gash across Kai's chest began to close. The torn skin pulled itself together, the bleeding stopping instantly as faint, golden light knit the flesh back into place. The lacerations on his forearms faded into faint pink lines, and the long cut across his cheek completely disappeared.
Beside them, Rei's eyes widened in sheer disbelief. As the music washed over his battered body, he heard a series of soft, muted snaps. The blinding agony in his side faded as his broken ribs realigned and stabilized. The dislocated bones in his right wrist popped back into their proper sockets, the terrible swelling draining away in seconds.
Mira finished the song with a long, fading note, lowering the flute with a soft exhale.
Silence reigned over the forest once more.
Juvia, Hisui, Arcadios, and Rei stood frozen like stone statues, their mouths slightly agape.
"H-Healing magic...?" Hisui stammered, pointing a trembling finger at Kai's completely restored chest. "A wide-area, high-density recovery spell?! From an artifact?!"
"Healing magic is a lost, ultra-rare discipline!" Arcadios declared, his brain struggling to process the visual evidence. "Only high-level specialized mages can cast recovery spells of that caliber, let alone an automated instrument!"
Mira stepped forward, holding the dark flute out toward Kai with a warm smile.
Kai didn't reach out for it. He just waved his hand lazily in the air. "Keep it."
Mira froze, her delicate fingers brushing against his bare forearm as she paused, her blue eyes blinking in surprise. "What? Kai... I can't keep this. It's your construct. It's invaluable."
Kai hummed, leaning his head back. "Tell me something I don't know, Clouds. I'm the one who spent an entire day rewiring its internal sonic channels. I know how valuable it is."
"Then why are you giving it to me?" she asked softly, her tone laced with genuine confusion.
Kai looked at her, his golden eyes softening just a fraction beneath his usual lazy mask. "Because right now, you can't use your Take-Over magic properly. And since you're traveling with me, I can't have you running around the kingdom with no way to defend or support yourself. I was planning on building you a custom defensive lacrima later, but until I get around to it... keep the flute. At least this way, if one of us gets stabbed, you won't have to just watch."
Mira stood entirely still, feeling the faint warmth lingering where her hand had touched his arm. A deep, radiant warmth blossomed in her chest. She knew Kai better than almost anyone—he would rather walk through fire than openly admit he cared about someone's safety in plain English. Disguising a deeply personal, protective gesture as a practical engineering convenience was the most 'Kai' thing he could possibly do.
She gently pulled the flute back, tucking it securely into the silk sash around her waist.
"Thank you, Kai," Mira said, her voice dropping into a sweet, teasing purr. "I'll take very good care of your little demon. And I'll be sure to play it every time you need a nap."
"Don't threaten me with a good time," Kai muttered. He turned back toward Rei, rolling his fully healed wrist. "Alright then. Now that we're fixed up, we can finally get back to—"
"ABSOLUTELY NOT!"
Hisui's voice echoed through the trees as she stamped her boot furiously on the ground, her face bright red with sheer royal frustration.
"You cannot just skip over this!" Hisui yelled, waving her arms dramatically in the air. "You just used a dark magic artifact to cast high-tier lost healing magic like it was nothing! You told the council a month ago that Lullaby was destroyed! And you still haven't explained who this man is, why you were fighting him, or what you are doing in this forest!"
Kai stared down at the tiny, screaming Princess, letting out a heavy, dramatic groan. He raised a hand, awkwardly rubbing the back of his neck as he looked at her.
"Can't we do this later, Radish Head?" Kai sighed, his voice dripping with reluctant exhaustion. "I am in the middle of a very important technical discussion right now. Why don't you just go back to the palace, do some royal princess stuff—I don't know, sign a decree, eat a fancy cake—and I promise I'll explain everything to you later tonight? And take Captain Hook and his metal army with you."
Hisui huffed loudly, puffing her cheeks out in absolute irritation. She glared up at his deadpan face for five long seconds, searching for any sign that he was taking her seriously. Finding none, she let out a long, defeated sigh, her shoulders slumping.
"Fine," Hisui muttered, pointing a stern finger at his nose. "But you are coming to my study tonight, Director. And you will tell me everything. No vague goat stories!"
Kai smirked, reaching down and giving her royal hair an aggressive, affectionate pat that completely ruined her neat hairstyle. "Yeah, yeah, sure. Now scoot."
Hisui huffed, trying to smooth her hair down as she turned back to Arcadios. "Captain, we are returning to Mercurius Palace."
Arcadios gave Kai one final, deeply suspicious glare before bowing to the Princess. "Understood, Your Highness. Escort unit, fall back!"
With a heavy clanking of iron armor, the Royal Guard fell into formation, surrounding Princess Hisui as they began their march back toward the city path.
Kai turned back to the remaining three girls—Cana, Mira, and Juvia—who were still standing in a small semi-circle, watching him with varying expressions of amusement and expectation.
Kai raised a brow, flicking his fingers toward the city trail. "What are you three waiting for? Shoo. Go do something productive. Didn't you say you wanted to go shopping and drinking in Crocus? Go do that. Or go with Hisui—she'll literally pay for your lunch if you tell her I sent you."
The three women exchanged glances.
Mira let out a soft, warm sigh, giving him an affectionate smile. "Fine. But please take care of yourself, Kai. Don't go blowing up any more forests before dinner."
Cana crossed her arms, turning on her heel with a smirk over her shoulder. "Yeah, don't think you're escaping that easily, slacker. We're not drinking in this city alone. You're coming with us tonight, whether we have to drag your body or not."
Juvia stepped forward, offering a formal, sweeping bow. "Juvia will return to the royal quarters and ensure a fresh pot of herbal tea is prepared for Kai-sama's arrival."
With that, the three Fairy Tail mages turned and began strolling down the forest path, rapidly catching up to Princess Hisui's armored escort. Within minutes, the sounds of their chatter faded away, until the only sound left in the clearing was the soft, lingering rustle of mountain wind through the sheared pine branches.
Kai stood in the center of the ruined space, taking a deep, long breath of the cool, pine-scented air.
Beside him, Rei slowly flexed his left hand, testing his newly healed ribs with a quiet, shocked expression. He looked toward the disappearing path, a faint, amused smirk touching his bruised face.
"Your companions are... remarkably enthusiastic," Rei noted softly, his voice returning to its calm, stoic baseline. "And unexpectedly caring."
Kai rolled his shoulders, letting out a short laugh as he walked over to the fallen log to retrieve his leather coat. "You haven't seen the half of it, dude. If you stick around them long enough, you lose brain cells by association."
Kai threw his leather coat over his shoulders, adjusting the collar before turning back to face the dark-haired swordsman. The lazy, joking persona receded just a fraction, replaced by the sharp, razor-focused gaze of the Director of Research.
"Well then," Kai said smoothly, leaning his hip against the fallen oak log and folding his arms across his chest. "Enough of the side shows. Let's talk business, shall we?"
Kai pointed a long finger straight at the silver-filigreed hilt resting at Rei's waist.
"What, exactly, is that sword of yours?"