KHR: Decimo Primo

The morning sun filtered through the curtains of Neuhaus's dormitory, casting a warm glow over the small kitchen. Tsuna stood at the stove, flipping pancakes with practiced ease. The sizzle of batter hitting the pan and the faint hum of the stove filled the room, creating a sense of calm that Tsuna had come to appreciate over the past two weeks. It was a far cry from the chaos of his first days at True Cross Academy, but he was starting to find his footing.

Two weeks. It had only been two weeks since Tsuna had arrived at the academy, and yet it felt like a lifetime. The rigorous schedule, the constant lessons, the late-night training sessions with Neuhaus—it was exhausting, but Tsuna couldn't deny that he was learning. Thanks to the habits Reborn had drilled into him and the strict training he'd undergone with Lal Mirch during his time in CEDEF, Tsuna had managed to keep up with most of the first-year curriculum. It wasn't easy, but he was determined not to fall behind.

Unlike many of his peers, Tsuna wasn't just adjusting to True Cross Academy's high school-level academics. Having already received an advanced education in Mafia school, where the curriculum far surpassed typical studies, Tsuna was academically on par with high school students despite being only nine years old. While the rigorous training and extensive coursework had shaped him into a competent candidate for Vongola's next boss, the truth was, Tsuna didn't particularly enjoy academics. He wasn't naturally inclined toward studying, nor was he particularly gifted in the field, but years of forced preparation had made him capable. The last three years had been a relentless cycle of learning, training, and fighting—conditioning him for the weight of leadership that he had yet to fully comprehend. He had pushed forward, not necessarily because he wanted to, but because it was expected of him. His parents, his friends, his mentors—everyone believed he would one day become the boss, and in turn, he had unconsciously internalized that belief.

Tsuna still wasn't sure why he needed to achieve it. He had never been asked what he wanted. Instead, he had been prepared for a destiny he hadn't chosen. Somewhere deep inside, he wondered—was this really what he wanted? But he had no answer, and so he continued, just as he always had.

He slid the last pancake onto a plate and glanced at the clock. 7:15. He had just enough time to eat before heading to his first class of the day. Sitting down at the small dining table, he dug into his breakfast, his mind already racing with thoughts of what the day might bring.

Despite being confined to the academy grounds during his internship due to Mephisto's restrictions, Tsuna communicated with his friends, parents, and coworkers in CEDEF. While he couldn't leave, he refused to be cut off from his world.

His phone vibrated, and he glanced at the screen to see a message from Basil. "Boss-in-training, how is your internship going? If it gets too overwhelming, remember, you've already conquered Mafia school. No school of exorcists can be worse than that!" Tsuna chuckled at the text. Basil was one of the few who understood the extent of their shared struggles. The constant combat training, the sleepless nights preparing for missions, the weight of expectations—if anyone could relate, it was Basil. Despite already being considered a member of CEDEF in practice, his young age kept him from being officially recognized on paper. Still, that didn't stop him from working just as hard as any veteran.

Then there was Naito Longchamp, whose energy seemed boundless even through a screen. "Tsuna! I met the CUTEST girl today! But she turned me down… again. Why is love so hard? Anyway, tell me about your exorcist school! Are there any cute girls there? I bet there are!" Tsuna sighed, shaking his head with a small smile. Naito's antics were as relentless as ever. Despite being the heir to the Tomaso Famiglia, he never seemed to take things as seriously as he should. But that carefree nature was what made him so unique. Alongside him, Lunga and Pantera were also going through their own internships, gaining experience in their respective fields.

Lunga's message was simple and to the point. "How's life at True Cross? Training as brutal as Mafia school? Let us know if you need anything." Pantera, ever the quiet one, had merely sent a single line: "Are you eating properly?" Tsuna appreciated the concern in her own way, even if she never said much.

Raul, his self-proclaimed rival, sent an entirely different kind of message. "You better not slack off in that exorcist school, Sawada! I refuse to let you get ahead of me! Next time we fight, I'm going to crush you!" Tsuna could practically hear the frustration behind those words. Raul had always been competitive, never quite letting go of that initial loss to Tsuna on the first day of Mafia school. He, too, was currently undergoing an internship, determined to prove himself as the strongest. Despite his aggressive nature, Tsuna knew that deep down, Raul was someone he could count on.

Dino also checked in, sharing a mix of encouragement and playful complaints. "Hope you're holding up okay, Tsuna! Reborn's training me into the ground. I swear, I thought being an official boss and a Mafia school graduate would mean a little less torture, but nooo. Anyway, he said once he's done with me, he'll be back to train you again, so brace yourself." Tsuna could almost hear the tired sigh in Dino's voice, but the lighthearted way he phrased it made Tsuna grin.

Bianchi, meanwhile, had fully joined the Mafia world, taking her family's business seriously. Her message was the usual mix of care and admonishment. "Don't forget to eat well, Tsuna. Proper nutrition is important." However, what caught Tsuna's attention the most was the update she gave. "Hayato finally contacted me. After running away two and a half years ago, he's been training hard to become an excellent mafioso."

Tsuna felt a wave of relief wash over him. Despite only meeting Hayato briefly during his bodyguard mission years ago, he had come to think of him as a friend. Knowing that he was safe and working toward his own goals reassured Tsuna more than he expected.

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His time at the True Cross Academy had been intense, but he was adapting. Aside from the usual exorcist training, he had learned about the fundamental forces that governed exorcists' powers. Unlike the Mafia's reliance on Flames, exorcists wielded holy energy—pure spiritual force channeled to combat demons. Most used an external source, like a specially consecrated weapon or scripture, since controlling it directly required immense talent and years of practice.

Sacred weapons, or Meister Tools, came in various forms. Swords infused with holy seals, firearms that shot sanctified bullets, talismans with embedded chants, and even musical instruments that could bind demons with sound-based incantations. Some exorcists wielded powerful relics, objects containing deep spiritual resonance passed down through generations.

One of the most crucial aspects of exorcist combat was the use of Holy Warding, a technique that allowed exorcists to create barriers against demonic corruption. These barriers could be temporary shields or complex seals that imprisoned demons. Mastering this art was essential, as demons constantly sought to invade human minds, corrupting them from within.

There was also the study of Demon Contracts. Some exorcists, particularly Tamers, bound lesser demons into servitude, controlling them through specialized rituals. This method was dangerous—if the contract faltered, the demon could easily turn on its master. Each summoned demon required precise control, and failing to maintain dominance often led to deadly consequences.

Tsuna found all of this fascinating but overwhelming. The more he learned, the more he realized how different this world was from the Mafia. Yet, there were similarities. The discipline, the constant need for vigilance, the way strength determined one's standing.

Finishing his letters, he leaned back, stretching. His parents had also responded to his messages, though in different ways. His mom, ever cheerful, had simply written about daily life and how much she missed him, including a note about how she had tried a new stew recipe. His dad's reply was more cryptic, as always.

"Keep training. You'll need it."

Tsuna sighed. That was typical of Iemitsu—vague yet ominous.

He had just started breakfast when footsteps approached. Neuhaus entered the kitchen with his usual stern demeanor. Tsuna had learned that Neuhaus rarely gave praise, and when he did, it was subtle—like allowing Tsuna to eat in peace before assigning him more work.

"Sawada," Neuhaus said curtly. "You'll be accompanying Juzo and Mamushi on a mission today. Consider it a practical test of what you've learned so far."

Tsuna blinked, mid-bite. "A mission? What kind of mission?"

"A routine demon-hunting assignment in the Forest District," Neuhaus replied. "It should be straightforward, but don't let your guard down. Demons are unpredictable."

Tsuna nodded, setting down his chopsticks. Today was the weekend, meaning there were no formal classes. It had mostly been a day for self-study and assisting Neuhaus with paperwork. He hadn't expected to be pulled into an actual mission, though.

What made it more surprising was that Neuhaus had initially planned to only involve Juzo and Mamushi. The past two weeks had seen Tsuna getting closer to his classmates—though not in the way he had expected. Rather than being seen as an equal, many of the students had started treating him like a younger sibling. They found him small, 'cute,' and often teased him like a mascot. It was embarrassing, but he couldn't deny that it had helped him integrate.

Neuhaus, unimpressed by this turn of events, had likely decided that today's mission was a good way to remind Tsuna that he wasn't here to be a novelty but an exorcist-in-training.

Tsuna finished his meal quickly, pushing away any lingering nerves. His first real mission as an exorcist-in-training was about to begin.

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An hour later, Tsuna found himself standing at the edge of the academy's Forest District, flanked by Juzo and Mamushi. The dense trees loomed before them, their shadows stretching long in the morning light. It was a stark contrast to the pristine halls of the academy, and Tsuna couldn't help but feel a sense of unease.

Unlike the controlled training grounds of the academy, the Forest District was untamed and unpredictable. The scent of damp earth mixed with something faintly metallic, and the distant sounds of rustling leaves and chittering creatures reminded him that they weren't alone. He knew there were demons lurking in the shadows, watching, waiting.

"Alright, kid," Juzo said, clapping Tsuna on the shoulder with enough force to nearly make him stumble. "Stick close to us and follow our lead. This should be a piece of cake."

Mamushi, ever more serious, crossed her arms and gave Tsuna a scrutinizing look. "The Forest District is home to low-level demons, but they can still be dangerous if you're not careful. Stay alert. Some of them are pests, others are ambush predators. They'll use the trees, the fog, and even the terrain itself to their advantage."

Tsuna nodded, trying to steady his nerves. He wasn't a stranger to combat—he had sparred against Reborn, fought trained Mafia assassins, and endured grueling training under Neuhaus. But all of that had been against humans.

This was different.

The idea of fighting actual demons made his stomach twist. No matter how dangerous human enemies could be, they at least followed certain instincts—fear, hesitation, logic. Demons weren't bound by the same rules. Some were mindless, acting purely on hunger and rage. Others were intelligent, cruel, and capable of tactics that no normal human would think of.

He flexed his fingers, feeling the faint heat of his Dying Will Flames simmering beneath his skin. Would it be enough against creatures of another world?

As they ventured deeper into the forest, Juzo and Mamushi began to explain the hierarchy of demons and their connection to the supernatural factions of the world.

"Demons come in all shapes and sizes," Juzo said, his tone casual despite the seriousness of the topic. "Some are mindless beasts, while others are cunning and intelligent. The ones we're dealing with today are low-level, but don't let that fool you—they can still pack a punch."

Mamushi nodded. "Demons exist in a hierarchy. The ones we fight most often are lesser demons—stray creatures, spirit-born beings, or things that slip through cracks between dimensions. But the real threats come from the higher demons. The ones that have names. Those have power, intelligence, and ambition."

Tsuna frowned. "You mean demons… have their own society?"

Mamushi gave him a sharp look. "Of course they do. You think they just exist to attack humans? No, they have their own world, their own rulers, and their own laws. In fact, a lot of the ones that come here are just outcasts or criminals from their own kind."

Juzo smirked. "Yeah, think of it like the Mafia, but even nastier. At the top, you've got Demon Kings. Each of them rules over a part of the underworld. just like in folklore demons like Satan, obviously, is the biggest name, but there are others—Leviathan, Beelzebub, Asmodeus, Lucifer… the list goes on exists and not just fiction. Each one has an army, and they're constantly scheming for power."

Mamushi continued, "It's not just demons either. The supernatural world is split into factions. The Three Factions—the Angels, the Devils, and the Fallen Angels—are in an eternal power struggle. Angels serve the Heaven System, Devils have their own society filled with nobles and warriors, and the Fallen… well, they're unpredictable."

Tsuna absorbed the information, feeling like he had stepped into an entirely different world. In the Mafia, there were power struggles, alliances, betrayals—but this? This was on a cosmic scale. Wars that had lasted for millennia, creatures that had ruled before humans even knew fire. It was overwhelming.

"So where do we fit into all this?" he asked.

Juzo shrugged. "Humans or exorcists? either way, we keep the balance. Some exorcist groups work with the Church, others are independent, and some…" He shot Mamushi a glance. "Well, some have ties with devils themselves. And of course, that's what we know from our side as an exorcist your Mafia and the Government also balance the supernatural in our world."

Mamushi scowled but didn't deny it. "There are cases where cooperation is necessary. Not all devils are hostile. Some just want to exist without getting caught in wars. But the Vatican doesn't see it that way. To them, anything not human is a threat."

Tsuna's mind whirled with the implications. Not all devils were evil? Not all demons were mindless killers. The more he learned, the less certain he was about anything.

But he didn't have time to dwell on it.

A guttural growl echoed through the trees.

Tsuna stiffened as the air grew heavy, a faint chill brushing against his skin. Something was watching them.

Juzo and Mamushi reacted instantly. Juzo reached for his broad blade, a weapon imbued with holy inscriptions, while Mamushi pulled out a talisman, her fingers glowing with spiritual energy.

A shape moved between the trees—large, hunched, and predatory. Its limbs were elongated, its fingers tipped with jagged claws. Its mouth, when it opened, revealed a row of needle-like teeth, and the glow of its red eyes cut through the shadows like embers in the dark.

"A Gashadokuro?" Mamushi muttered, recognizing the type. "No… smaller. But still dangerous."

The demon moved fast. One second, it was in the shadows—the next, it lunged, claws flashing.

Tsuna barely had time to react before Juzo intercepted it, his sword slashing in a precise arc. The creature shrieked as the blade cut deep, the wound sizzling as the holy energy burned through its flesh. But it wasn't done yet.

Tsuna's instincts screamed at him to move, and he barely dodged as a second demon, smaller but just as vicious, leaped from the underbrush, aiming for his throat.

He reacted on instinct. Flames burst from his hands, his Dying Will igniting in response to the threat. He punched forward, and the moment his knuckles connected with the demon's torso, a blast of orange flames erupted, sending the creature flying into a tree.

It hissed, writhing in pain, but it wasn't dead.

Tsuna gritted his teeth. This wasn't like fighting human opponents. He couldn't predict their movements the same way, couldn't read their body language like he was used to. These things weren't hesitant. They didn't fear pain.

He had to change how he fought.

Juzo and Mamushi were already moving in sync, striking with precision. Mamushi used talismans to bind the demons in place while Juzo struck the killing blows. It was efficient—calculated. They had done this a hundred times before.

Tsuna, meanwhile, was still adjusting. He forced himself to focus, dodging another swipe before channeling more Flames into his palms. This time, when he struck, he poured his will into it, aiming to incinerate it rather than knock it back. The demon shrieked as the flames consumed it, turning its body into blackened ash.

He exhaled, heart pounding.

His first real battle against demons, and it was far from over.

Juzo grinned. "Not bad, kid. Let's see if you can keep up."

Tsuna clenched his fists, determination burning in his eyes.

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As the demon emerged from the shadows, Tsuna felt his heart pound against his ribs. This was unlike any fight he had experienced before. Up until now, he had only ever fought against humans—mafia members, assassins, and trainers who at least fought with a semblance of logic and predictability.

This? This was something else entirely.

The demon's sheer presence was suffocating, its aura thick with malice. Its crimson eyes locked onto him, its jagged teeth gleaming as it let out a guttural snarl. It didn't move with the hesitation of a human combatant; it lunged, wild and unpredictable, driven purely by instincts and bloodlust.

Tsuna barely had time to ignite his Dying Will Flames before the demon's massive clawed hand came crashing down toward him. He twisted his body, dodging to the side at the last second as the ground where he had been standing exploded into a shower of dirt and shattered stone.

Juzo was already moving, his massive cleaver-like sword swinging with brutal force. The blade connected with the demon's arm, sending a spray of black ichor into the air. The creature howled but barely recoiled, its wound sizzling as its dark energy attempted to mend it.

"This thing's tougher than it looks!" Juzo grunted, gripping his weapon tightly.

Mamushi darted forward with elegant precision, her katana flashing as she carved glowing sigils into the air. The exorcist seals ignited, forming a web of light around the demon. "Binding Circle!" she called out, and the sigils expanded, wrapping around the demon's limbs and slowing its movements.

Tsuna saw his chance. His Sky Flames flared to life around his fists, orange embers licking at his skin. He dashed forward, weaving through the battle with agility, his flames boosting his speed. With a burst of energy, he leaped onto the demon's back and drove his fist into its shoulder, the impact sending a ripple of heat through its body.

And yet—

The demon barely reacted.

Tsuna felt his stomach drop. His flames had power, but they lacked the sheer destructive force he needed. Unlike the raw burning intensity of his Reborn's Sun Flames or the piercing properties of Storm Flames, his Sky Flames merely radiated warmth. It could enhance his physical abilities, but it wasn't an immediate killing force.

The demon snarled and twisted violently, forcing Tsuna to jump back before its jagged tail could strike him.

"You're still treating this like a fight against humans!" Juzo barked at him as he swung his cleaver downward. "Demons don't hesitate! You hesitate, you die!"

Gritting his teeth, Tsuna focused. If his Sky Flames weren't strong enough to deal damage, then he had to get creative. He flicked his hand, summoning a faint mist of his Mist Flames. Unlike Sky, his Mist Flames were barely combat-oriented at his current level, but they were enough for small illusions.

The demon's eyes glowed as it lunged toward him—only to suddenly reel back as a second Tsuna appeared in its vision. The illusion flickered, but it was just enough to disorient it.

Mamushi seized the moment, dashing forward and slicing a deep gash into its leg.

Tsuna exhaled sharply. His control over illusions was weak, but the brief distraction had worked. He pivoted, reinforcing his own movements with Sun Flames now, pushing his exhausted body further. He could feel the regenerative properties working, dulling the sting of minor scratches and bruises forming from all his dodging.

But compared to Juzo and Mamushi—who fought with practiced efficiency—Tsuna felt woefully behind. Their strikes were deliberate, their techniques honed through rigorous exorcist training. He could barely keep up.

The demon roared again, its energy surging. The sigils Mamushi had carved were beginning to wane, their glow dimming as the creature struggled against them.

Tsuna clenched his fists.

He refused to be dead weight.

Gathering his flames, he lunged again, this time aiming not for damage, but to weaken the demon's movements. He let loose a burst of Sky Flames, pushing against the demon's form—not enough to burn, but enough to disrupt its balance. At the same time, he wove a flicker of Mist Flames into his movements, making his strikes seem unpredictable.

Mamushi noticed the shift and adjusted accordingly, moving into a position to strike its now-exposed side. "Good! Keep it unsteady!"

Juzo grinned, slamming his sword down with brutal force. "You're getting the hang of it, kid!"

Tsuna didn't have time to respond as the demon let out a final, bloodcurdling shriek. Between their combined assault and its accumulating wounds, its body finally gave out. With one last shudder, it collapsed to the ground, its form dissolving into black ash.

The forest fell silent once more.

Tsuna panted, his flames slowly flickering out. His body ached from exertion, but more than that, his mind was still reeling. This fight had exposed so many weaknesses. His flames were strong, but he lacked the refined control and deadly efficiency of an exorcist. His techniques were still rooted in human battles, where instinct and strategy played a greater role than pure survival against relentless monsters.

Juzo clapped him on the back, nearly knocking him over. "Not bad for your first real demon fight! You didn't die, so I'd call that a win!"

Mamushi gave him a long look before nodding. "You're not an exorcist, but you have potential. You need to refine your flames more. Right now, they're raw power, but that won't be enough against stronger demons."

Tsuna exhaled, nodding. He knew she was right.

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As the adrenaline slowly drained from Tsuna's body, the exhaustion hit him like a tidal wave. His gauntlets, still faintly glowing from the heat of the battle, felt heavier now. His knees buckled slightly as he sank to the ground, the weight of the fight catching up to him. He didn't know how long he had been standing, but now, with the threat vanquished, his body could no longer hold on.

Juzo slapped him on the back, almost sending him toppling over, but Tsuna managed to steady himself.

"Not bad, kid," Juzo said, his usual grin creeping back onto his face. "You've got guts, I'll give you that."

Tsuna chuckled weakly, still panting heavily. He didn't feel like he had guts; he felt like a pile of worn-out muscles and burnt nerves. But he didn't say that. He couldn't, not when he had to hold up a brave front in front of his mentors.

Mamushi, usually so composed, looked down at him with a rare, softer expression. "You held your own. That's more than most first-years can say," she said, her tone more approving than Tsuna had ever expected.

"Yeah, kid. You didn't run. You didn't freeze up." Juzo added, nudging him with his elbow. "That's a start. A good one, too."

Tsuna nodded, managing a faint smile despite his aching body. But before he could get any words out, Mamushi's sharp eyes narrowed. She crouched down, pushing aside some of the demon's ashen remains, her fingers brushing against something small and glowing.

Tsuna's senses screamed at him to stay alert. There was something off about this scene, something that gnawed at the pit of his stomach.

"What's this?" Mamushi muttered under her breath, her gloved hand hovering over the small shard that pulsed with an unsettling, dark energy.

Juzo's face darkened as he stepped closer. "That's not normal," he said, his voice losing some of its usual bravado. "Demons don't usually leave behind... whatever that is."

The shard glowed ominously, shifting between shades of dark crimson and violet. Tsuna could feel the malevolent energy radiating from it, a cold shiver running down his spine. He didn't need to get any closer to know it was bad news. Whatever this thing was, it wasn't just a byproduct of a fight.

Mamushi's eyes flickered to the sky as she stood up, her expression grim. "We need to report this to Neuhaus. Something's not right."

Tsuna's pulse quickened. Neuhaus. The name rang through his mind, but it wasn't the first time he had heard it. Neuhaus was the academy's head, a person who handled more than just the everyday tasks. He was someone who managed the dark secrets, the missions too dangerous or too sensitive for the average student or exorcist. And if Neuhaus had to get involved, it meant things were worse than they seemed.

Juzo glanced at Tsuna, his smile fading just a bit. "Kid, get up. We're heading back to the academy. We'll sort this out there."

As they made their way through the forest, Tsuna couldn't shake the unease gnawing at him. The demon's last words echoed in his mind. A great disturbance... He hadn't had time to process it in the heat of the moment, but now, in the quiet after the battle, those words felt like a warning. A warning of something far bigger and far worse than the fight they had just endured.

The wind rustled through the trees, but the weight of the situation felt like it held the air still, suffocating him with every step.

Mamushi's voice broke the silence, though it was softer now, as if she too felt the growing tension. "It's not just about the shard. Something's coming. Something worse than what we just faced."

Tsuna didn't reply, but his mind was racing. He didn't know exactly what Mamushi meant, but he had a sinking feeling. The way the demon had fought, the way it had been so relentless, so different from anything Tsuna had seen before—it was a sign. A sign that this was only the beginning.

The three of them trudged back to the academy, the weight of the task ahead pressing heavily on Tsuna's shoulders. He hadn't expected a fight like this. He hadn't expected the aftermath to bring more questions than answers.

They passed through the academy gates, the familiar stone walls giving Tsuna a small sense of security, though it felt fleeting. Inside, things were always more complicated than they seemed. He didn't even get to rest before Mamushi and Juzo were already preparing to report the incident to Neuhaus.

As Tsuna sat in the cold, sterile hall of the academy's briefing room, the quiet hum of lights above his head seemed to mock his uncertainty. His body was bruised and battered, but that was the least of his concerns now. The disturbance, the shard, the demon's warning—they all circled in his mind like a storm, churning faster and faster, but he had no way to know where it would hit next.

For now, all Tsuna could do was prepare. But what did he need to prepare for? He couldn't answer that. The path ahead was dark, more obscure than ever.

And yet, there was something else inside him now. A flicker of resolve, a spark of determination he hadn't realized was there until now.

Whatever was coming, Tsuna would face it. Not just because he had to—but because, for the first time in a long while, he felt like he had something worth fighting for.

The mission had been a success. But it had also raised more questions than answers. Tsuna couldn't shake the feeling that everything was changing, and he was standing right at the edge of something far greater than he could have imagined.