Chapter 6: Shiro, Rin's mentor!

Days had passed since Rin awakened her second core and since the attack on the Academy. Since then, she and Shiro had been walking through the dense woods, the air thick with the scent of moss and pine. “Hey… uh, Shiro—” Rin started, glancing around nervously. “Call me Sensei, Rin,” Shiro interrupted calmly, his eyes scanning the forest like he was expecting something. “Yes… Sensei,” Rin replied, straightening her posture. “But… where are we going? Why are we out here in the woods?” Shiro didn’t answer immediately. He slowed his pace, letting Rin catch up. “Out here,” he said finally, “you won’t be distracted. No one to impress, no rules… just you, me, and your cores.” Rin’s eyes widened. “My cores… you mean… you’re going to train me?” Shiro nodded, a faint smile tugging at the corner of his lips. “Exactly. But training you won’t be easy. You’ll push past your limits. And you might get hurt. A lot.” Rin clenched her fists, sparks of energy flickering faintly over her knuckles. “I… I don’t care. I’m ready, Sensei.” Shiro’s eyes glinted with approval. “Good. That’s the spirit. But remember—strength isn’t just about power. Control is everything. And out here, you’ll learn both.” Shiro said. They walked in silence until the sound of rushing water grew louder, the trees thinning to reveal a towering waterfall crashing into a crystal-clear pool below. Mist hung in the air, cool and heavy, catching the sunlight in faint rainbows. Shiro stopped and pointed. “There,” he said, his voice firm but calm. “See that rock wedged between the waterfall and the cliff wall?” Rin followed his gaze, spotting the slick, moss-covered stone surrounded by a relentless curtain of water. Her brows furrowed. “I want you to sit there,” Shiro continued. “Cross-legged. Meditating. The water will crush you if you falter. But if you can focus—if you can steady your cores—you’ll find clarity.” Rin swallowed hard, the roar of the falls suddenly deafening. “…You want me to meditate under that?” Shiro smirked faintly. “Exactly. If you can keep your mind sharp while drowning in chaos, you’ll be ready for the real training.” Rin stepped onto the moss-slick rock beneath the roaring waterfall, water hammering down like a mountain crashing on her shoulders. Every breath felt like dragging air through ice, but she forced herself into a cross-legged position. “Focus,” Shiro’s voice carried over the thunder of the falls. “Not on the lightning you’ve already mastered. I want you to reach deeper. The Beast Core. Find it. Control it.” Rin shut her eyes, shutting out the sound as best she could. At first, the familiar hum of her Lightning Core sparked in her chest—calm, sharp, obedient. But when she tried to reach further… she felt it.mThe Beast Core. It wasn’t calm. It wasn’t sharp. It was a storm of claws and fangs, of pounding instincts telling her to fight, to leap, to rip free of the water crushing her down. The moment she touched it, her breath hitched and her eyes flashed faintly gold. Her nails dug into the stone beneath her. The waterfall’s pressure grew heavier, and the Beast Core surged in response, wild energy tearing through her veins. A growl rumbled from her throat before she even realized it. It’s too much… I can’t… hold it— The Beast Core burst outward. A shockwave of raw primal force exploded around her, scattering the waterfall for a split second, spraying mist in every direction. Rin was thrown back into the pool below with a splash, gasping for air. She surfaced, chest heaving, golden light still flickering in her eyes before fading. Shiro stood on the bank, arms folded, his gaze sharp but not unkind. “You touched it,” he said simply. “For a moment, you grasped the Beast Core’s essence. But you let it rule you instead of ruling it.” Rin panted, gripping her chest. “It… it’s nothing like my Lightning Core. It doesn’t listen. It just… wants to break free.” Shiro smirked faintly. “Exactly. That’s why this training matters. You don’t need to cage the beast, Rin. You need to teach it to obey.” Rin surfaced, gasping for air as she dragged herself onto the bank. Water streamed down her face, her body aching from the crash of the falls. Shiro’s voice cut through the roar. “Don’t just sit there. Get back up. Again.” Her eyes widened. “Already? But—” “No excuses,” Shiro said firmly, his arms crossed. “The beast won’t wait for you to be ready. Now move.” Rin clenched her fists, frustration flashing across her face. But she forced her shaking legs to stand. Step by step, she made her way back across the slippery stones, climbing once more onto the rock beneath the waterfall. She sat cross-legged, the crushing water hammering against her shoulders, eyes tightly shut as she sank deep into meditation. When she opened them, the world had shifted. She was no longer on the rock beneath the waterfall. She stood in a massive chamber, water rising to her knees, rippling around her like a shallow, restless sea. Rin’s gaze swept across the room, taking in the walls that stretched impossibly high, shimmering faintly as if alive. When she turned, her breath caught. Before her stood a colossal caged door, its bars twisting in intricate patterns, almost like they were carved from obsidian and energy itself. At the center of the spiral-shaped lock, a glowing, pulsing light throbbed—her Beast Core, waiting, wild and untamed. A single eye appeared behind the cage, glaring at her. Its pupil was a jagged diamond, sharp and chaotic, alive with a feral intelligence. It burned with a power that felt ancient, untamed, and completely aware. When it locked onto Rin’s gaze, she could feel it probing her very soul, weighing her, testing her. The room seemed to shrink around her, the water at her knees churning as if the Core itself was alive. It wasn’t merely watching. It was judging. Waiting. Daring her to try. “What… is… it… you… WANT!?” a deep, guttural voice bellowed from within the cage. The sound rattled the air and vibrated through Rin’s chest, like thunder striking inside her bones. The jagged diamond-shaped eye glared at her, pulsing with every word, as if the very essence of the Beast Core was speaking directly into her mind—and testing her courage. Rin staggered back slightly, her heart hammering. The water around her legs rippled violently, reacting to the surge of energy. “What… are… you…?” Rin whispered, fear threading through her voice, her knees trembling in the shallow water. “I am your beast… inside your core… the Nine-Tailed Fox…!” the voice growled, deep and resonant, echoing off the chamber walls. The jagged diamond-shaped eye glared at her, unblinking and full of feral intensity. Suddenly, the eye moved upward, and another appeared in front of her, larger and just as fierce. Both eyes now locked onto hers, glaring down as if weighing her worth, daring her to face what she had carried unknowingly inside all this time. The water rippled violently around her legs, the very air trembling under the presence of the Beast Core. Rin felt a mix of awe and terror—the fox inside her wasn’t just power; it was a living, testing force, and it had noticed her. “How long have… you… been… here…?” Rin’s voice trembled, a mix of fear and awe. “I’ve been here… since you were born…” the deep, guttural voice rumbled, each word vibrating through her chest like rolling thunder. Outside the cage, the water began to churn violently. Dark red bubbles surfaced, growing larger and larger, swirling together as if forming a shape. Slowly, an ominous outline took form—like a massive hand, fingers stretching toward her, reaching out from the swirling liquid. Rin’s eyes widened, her heart hammering. It’s… alive. It’s trying to touch me… The jagged diamond-shaped eyes glared at her from the cage, unblinking, almost laughing with anticipation as the hand grew closer, pulsating with raw, chaotic energy. Shiro’s eyes sharpened as he watched from the bank. Even while Rin remained perfectly still under the waterfall, half of her body began to shimmer with a strange, dark red aura. The aura bubbled and twisted, flowing like liquid fire over her skin, and from it, faint shapes began to emerge. Tails—long, ethereal, wriggling like living shadows—started forming along her back, writhing gently with each pulse of energy. Despite the waterfall crashing down on her, Rin’s posture didn’t falter. She remained cross-legged, eyes closed, deep in meditation. Yet the Beast Core inside her was stirring, its chaotic power leaking outward for Shiro to witness. Even from the shore, he could feel the raw intensity radiating from her—a living, untamed force that demanded recognition and respect The massive hand finally finished forming, its dark red energy swirling and coiling like living fire. Before Rin could react, it shot forward and grabbed her. Her eyes widened in shock as it lifted her effortlessly, dragging her toward the spiral-shaped lock at the center of the cage. The Beast voice thundered in her mind, raw and commanding: “Unlock it… NOW! I’m tired of being trapped inside this human body!” Rin’s heart raced. The spiral glowed violently, pulsing in time with the roar of the Beast Core. Every instinct screamed at her to resist, to run—but she felt herself drawn closer, as if the hand was guiding her toward a destiny she didn’t yet understand. “Stop it… stop it… STOP IT!!!” Rin screamed, her voice echoing through the chamber. The Beast hand tightened around her, but something inside her snapped. Lightning surged uncontrollably from her Lightning Core, crackling and arcing across her body. The raw energy struck the massive hand, shattering it into pieces of dark red energy that scattered into the air like sparks. The force of the lightning threw Rin backward, landing her hard in the shallow water, gasping for breath. Her chest heaved, eyes wide and glowing faintly from the residual sparks. For the first time, she realized just how dangerous—and alive—her Beast truly was. The spiral lock glowed in the distance, the Beast Core’s voice now a low, rumbling growl: “You cannot hide from me forever…” Her eyes snapped open, the world around her spinning. She stumbled forward, falling into the shallow water beneath her. The cold hit her like a shock, soaking her completely, but it barely registered. Her chest heaved, muscles trembling, and her mind raced, still reeling from the raw surge of energy she had just unleashed. For a moment, everything was silent except the steady crash of the waterfall. Rin’s hands sank into the water, grounding herself, trying to catch her breath—and trying to make sense of the wild, untamed power that had just erupted from within her. From the bank, Shiro’s eyes widened, his arms slowly dropping from their crossed position. He hadn’t expected such raw power to surge from Rin so suddenly. “That… that was impressive,” he muttered under his breath, a rare hint of admiration threading through his normally calm voice. His sharp gaze studied her closely, noting the way her body still radiated lingering energy, the faint sparks of lightning dancing across her skin. “She’s tapping into her cores in a way I didn’t think possible,” he continued, voice low but firm. “Not just the Lightning Core… the Beast Core too. She’s stronger than I gave her credit for.” A small, approving smirk tugged at his lips as he shook his head slightly. “Good. Very good. But this is only the beginning, Rin. You’re far from mastering it.” Rin sank into the shallow water, her chest heaving, legs trembling as the adrenaline faded. Her arms drooped limply at her sides, and the faint sparks of lightning across her skin flickered weakly before fading. Shiro’s eyes softened slightly as he watched her struggle to catch her breath. Despite the exhaustion etched across her face, he could see the fire still burning within her—the raw, untamed potential of her Beast Core. “That… that was impressive,” he muttered under his breath, a rare hint of admiration threading through his usually calm tone. “Even like this… she’s stronger than I expected.” He shook his head slightly, a faint smirk tugging at his lips. “Rest for now, Rin. But know this—this was only the beginning. You survived the first surge. The real challenge is learning to control it.” Rin barely nodded, too drained to speak, her body trembling as she sank lower into the water, letting herself recover while the roar of the waterfall crashed around her. Rin staggered forward, water dripping from her soaked clothes as she pushed herself back toward the stone at the center of the waterfall. Her legs trembled, every muscle in her body screaming at her to stop, but her eyes still burned with determination. “I can… keep… going…” she muttered, clenching her fists. “I can… do… this!” From the shadows of the cavern, Shiro watched in silence. His usual cold, calculating expression softened for just a moment. He hadn’t expected her to push past the fox’s influence so soon—or to resist with such raw force. The lightning she unleashed still lingered in the air, crackling faintly around the stone. “…Impressive,” Shiro murmured, his sharp eyes narrowing in thought. She’s completely drained, yet still standing. That stubborn willpower… she might just survive this training after all. He folded his arms, considering his next move. If she has the strength to keep climbing after being shattered, then it’s time I push her further. The real trial begins now. Rin steadied herself on the slick stone, water pouring over her shoulders as she dropped into a shaky meditation pose. Her breaths came ragged, but her eyes burned with stubborn fire. “Rin! Stop this immediately!” Shiro’s voice cut through the thunder of the waterfall. “You can’t keep going if you’re just going to push past your limits all at once!” “I…can do this…” she whispered, forcing her body upright despite the trembling in her limbs. Shiro’s eyes narrowed. In an instant, his form flickered—then vanished. The air cracked with displaced energy as he appeared right before her. Before Rin could react, his hand gripped her wrist firmly. “Enough.” The world warped around them as Shiro pulled her close. A surge of energy enveloped them both, and in the blink of an eye, the roar of the waterfall vanished. They reappeared on solid ground at the base of the cliffs, away from the rushing water. Rin stumbled, nearly collapsing as Shiro kept her steady with an unyielding grip. “You’re reckless,” he muttered, his tone sharp but edged with something that almost sounded like concern. “If I hadn’t stopped you, you would’ve destroyed your body before your training even truly began.” Rin’s knees wobbled, her vision blurring as exhaustion clawed through her body. She tried to steady herself, tried to take a deep breath—but her strength was gone. In an instant, her eyes fluttered shut. Her arms fell limply to her sides, and her body sagged against Shiro’s grip. She had fainted. Shiro’s eyes softened slightly as he adjusted his hold to keep her steady. The raw power she had unleashed moments ago still hummed faintly through the air, but now her body needed rest. “You pushed too far,” he muttered, his tone low and controlled. “No one can survive this kind of training without learning their limits first.” He glanced down at her, still unconscious, then toward the waterfall behind them. Tomorrow… we start again. But she’ll be stronger, or I’ll make sure she doesn’t break herself before she learns control.