"Yes," she said, her voice surprisingly steady despite the tears still tracing paths down her cheeks. "I'll do it. Train me."
A wide, almost relieved grin spread across Rimuru's face, a spark of his old mischievousness returning. "Alright then!" he said, his voice filled with a newfound, invigorating purpose. He extended a hand towards her. "The path ahead will be tough, tougher than anything you can imagine. But I'll be with you every step of the way. Come with me, Lucy."
The moon, a sliver of silver in the rain-washed sky, cast long, dancing shadows over the once-beautiful Heartfilia estate. Lucy hesitated for only a moment, her gaze fixed on Rimuru's offered hand. Then, with a deep, shuddering breath, she placed her small, trembling hand into his. It was surprisingly warm, reassuring.
In a blink, the ravaged garden, the scent of death, and the falling rain vanished. They reappeared in a secluded, ancient forest, sunlight dappling through a thick canopy of emerald leaves. The air was fresh, alive with the sounds of nature.
"This," Rimuru announced, gesturing around them with a sweep of his arm, "will be our new home, and our training ground."
Lucy looked around, her eyes wide, still clutching the locket. The abrupt change of scenery was disorienting, but there was a strange sense of peace here, a stark contrast to the horror she had just escaped. She took a deep breath, the scent of pine and damp earth filling her lungs. She turned back to Rimuru, her small face set with a grim determination that seemed too old for her years.
"I'm ready," she said, her voice quiet but firm.
And so, it began. The first year was, to put it mildly, brutal. Rimuru, despite his gentle demeanor when he'd found her, was an unyielding taskmaster when it came to fundamentals. He knew that without a solid foundation, any advanced techniques would be useless.
"Again, Lucy! Lift it!" Rimuru's voice echoed through the small clearing they'd made their own. Before her stood a thick log, easily twice her weight. Her small arms, already trembling from previous attempts, strained against the rough bark.
"I… can… DO THIS!" Lucy gritted out, her teeth clenched, every muscle in her five-year-old body screaming in protest. Tears of effort and frustration pricked at her eyes, but she blinked them back fiercely. The image of her parents' smiling faces, then their lifeless forms, flashed in her mind. With a guttural cry, she heaved, the log rising an inch, then two, before she managed to hoist it to her chest, staggering but upright.
Rimuru watched, a flicker of surprise and admiration in his eyes. She's got incredible willpower for a kid her age, he thought. More than I've seen in most adults. "Good! Excellent focus! Now, controlled descent. Don't just drop it."
Lucy lowered the log, her breath coming in ragged gasps, collapsing onto the soft earth beside it once it was down.
"Rest for ten minutes," Rimuru said, his voice softer now. He tossed her a waterskin. "Then, we work on stamina. Long-distance running until dusk." He saw the exhaustion etched on her face, the slight droop of her shoulders, but also the stubborn set of her jaw. "Tomorrow," he added, a glint in his eye, "we begin basic combat drills. Hand-to-hand. You need to learn how your body moves, how to make every ounce of your strength count."
Days bled into weeks, weeks into months. The forest became Lucy's world. She learned to read the subtle shifts in the wind, the language of the rustling leaves. Rimuru taught her not just to fight, but to survive – how to find food, build shelter, track. Every evening, by the light of a crackling fire, he would sometimes, carefully, ask about her parents, letting her talk, letting her grieve. He never pushed, but he listened, his presence a steady anchor in the storm of her emotions. He even, very occasionally, shared heavily redacted, G-rated snippets of his "adventures," making her giggle despite her sorrow – a small, precious sound that warmed him more than any sun.
The second year, when Lucy had turned seven, brought the introduction of weapons. Rimuru started her with a simple wooden staff, then moved to a bokken – a wooden practice sword.
"Focus, Lucy! Your stance is too wide, you're off-balance!" Rimuru's voice was sharp as he parried her clumsy swing with his own bokken. They circled each other in their practice clearing, the rhythmic thwack-thwack of wood on wood echoing through the trees. "Don't just swing wildly! Anticipate! Where am I going to strike next? Where are your openings?"
"Right!" Lucy panted, sweat dripping down her temples, her knuckles white as she gripped the bokken. She feinted low, then lunged, aiming for his side. He blocked it easily, but a small smile touched his lips.
"Better! Much better! You're learning to think. But faster! Your movements are still too hesitant!"
She pushed herself, day after day. Her small hands, once soft, were now calloused. Scrapes and bruises were her constant companions. But with every ache, with every drop of sweat, she felt a sliver of control returning, a sense of purpose solidifying. The raw, burning grief was still there, a constant fire in her belly, but now it was being channeled, forged into something sharp.
By the time the third year of their unconventional training hit, and Lucy was a whip-cord strong eight-year-old, Rimuru often found himself staring, his jaw practically scraping the forest floor.
"Strategy, Lucy! Strategy is key!" he yelled, narrowly dodging a flurry of surprisingly powerful strikes from her bokken. She was faster, much faster than he'd anticipated she'd be at this stage. "Don't just rely on brute force! Outthink your opponent!"
Lucy, her breath coming in controlled pants, didn't respond verbally. Instead, she feinted a lunge to his left, drawing his guard, then, with a speed that belied her age, spun on her heel, her wooden sword whistling through the air in a tight arc aimed at his exposed flank. CLACK! Rimuru barely managed to bring his own bokken up in time for a desperate block, a surprised grunt escaping him. The impact jarred his arm.
He stepped back, lowering his weapon, a wide, genuine grin spreading across his face. "Whoa! Now that was clever! Very clever indeed!" He was genuinely impressed. "You've learned well, Lucy! Exceptionally well!"
"Thank you, Sensei!" Lucy panted, lowering her sword. A sheen of sweat glistened on her forehead, but her eyes, usually so serious during training, held a spark of pride.
Sensei? Rimuru thought, a surprisingly warm, fuzzy feeling spreading through his chest. Huh. That's… kinda nice. He stepped forward and placed a hand on her small, sturdy shoulder. "You've come so far, Lucy. Farther than I ever expected, if I'm being completely honest."
He looked at her, truly looked at her. The small, grieving child he'd found was still there, hidden beneath layers of hard-won strength and discipline, but now she was… formidable. Seriously, what the heck is this kid made of? he mused internally. If she'd had this kind of drive in the original anime, she'd be giving Mirajane a run for her money by the Tenrou Island arc! Erza? Gildarts?! Maybe even them, eventually! What the actual…! And those strength feats! For an eight-year-old to be pressing logs nearly three times her weight now? That's insane! He remembered his own early training with Veldora and the others. This girl's progress, her raw talent married to this fierce determination, was on a whole other level for a human of her age.
"You're pretty amazing, Lucy," he said aloud, the grin softening into a genuine smile of affection and pride. "You know that, right?"
A faint blush, a rare sight indeed, touched Lucy's cheeks. She looked down at her worn bokken. "I just… I want to get stronger, Sensei. For Mama and Papa. So I can do what I promised."
Rimuru's smile softened further, a pang of understanding hitting him. Right, the revenge thing. He knew, deep down, that he had to help her find a path beyond that all-consuming fire, but he also intimately understood the power of such a driving force. "And you will, Lucy. You will get stronger. I promise you that." He paused, a mischievous glint returning to his eyes. "But… we're not done yet. Not by a long shot."
"What's next, Sensei?" Lucy asked, her weariness momentarily forgotten, her eyes sparkling with anticipation.
"Well," Rimuru said, rubbing his chin thoughtfully. "You've got the strength down. Your speed is incredible. And your strategic thinking is… surprisingly devious." He winked. "But… what about the finesse?"
"Finesse?" Lucy tilted her head, her brow furrowed in confusion.
"Swordsmanship!" Rimuru grinned, snapping his fingers with a flourish. A sleek, perfectly balanced training sword, not wood this time but a dull-edged metal that still gleamed, appeared in his hand. "Proper sword techniques, Lucy! The kind of elegant, powerful forms that make your opponents go 'Whoa!' right before they hit the ground unconscious." He tossed a similar blade to her, which she caught with reflexive ease. "Let's start with the basics. Stance, footwork, the art of the draw, parries, ripostes…"
This is gonna be fun, he thought, a playful smirk dancing on his lips. I'll show her all the flashy moves from my favorite sword-wielding anime characters! And maybe, just maybe, with her talent, she'll not only get her justice but also become the strongest mage Earthland has ever seen! Now that would be a story worth experiencing!
He drew his own training sword with a dramatic, exaggerated shiiiiing sound he made himself, striking a pose. "Alright, Lucy," he declared, his voice booming theatrically. "First lesson: the art of the dramatic entrance! You gotta have style, kid!"
Lucy, startled at first by his sudden change in demeanor, stared for a second, then a small giggle escaped her lips, quickly followed by another. Soon, she was laughing, a bright, clear sound that echoed through their clearing, a sound Rimuru hadn't heard nearly enough. Her eyes, for a moment, shone with the pure, unadulterated joy of a child.
"Dramatic entrance, huh?" she chirped, attempting to mimic Rimuru's flourish. Her small arms and the unsharpened metal blade made it look more adorable than intimidating, but the intent was there. "Like… like this, Sensei?" Fwsh!