Fairy Tail:Celestial Tempest

Months flew by, a whirlwind of training and laughter. Lucy, now a lean, powerful eight-year-old, moved with a grace that belied her age. She'd mastered swordsmanship, martial arts, and combat techniques with an almost unsettling speed.

"Alright, Lucy! One more time!" Rimuru yelled, dodging a lightning-fast kick. "Show me that spinning strike you've been working on!"

Lucy grinned, her eyes sparkling. She spun, her wooden sword a blur, creating a miniature whirlwind of leaves and dust.

"Whoa! That's it!" Rimuru exclaimed, clapping his hands. "You've got it! You're a natural, Lucy!"

Seriously, this kid is terrifyingly good, he thought, wiping a bead of sweat from his brow. She's mastered everything I've thrown at her! Everything! At eight years old! This is beyond anything I've seen!

He glanced at the setting sun. "Alright, that's enough for today. Tomorrow's a special day, you know."

"My birthday!" Lucy beamed. "I can't wait!"

"That's right," Rimuru chuckled. "And I've got a little something special planned."

The next morning, Lucy woke to the smell of something delicious. She rushed out of her makeshift room, her eyes widening at the sight of a small, but festive, celebration.

"Happy birthday, Lucy!" Rimuru grinned, holding out a beautifully wrapped package.

"Sensei! You didn't have to!" Lucy gasped, her eyes filled with tears.

"Nonsense!" Rimuru said, pushing the gift into her hands. "Open it!"

Lucy tore open the wrapping paper, her eyes widening as she revealed a gleaming sword. The blade shimmered with a faint, magical aura.

"Sensei… it's beautiful!" she whispered, her fingers tracing the intricate carvings on the hilt.

"It's made from a special metal," Rimuru explained, "enchanted to be incredibly durable and sharp. It'll be perfect for you."

"Thank you, Sensei!" Lucy cried, throwing her arms around him.

Rimuru patted her back, a warm feeling spreading through him. "You've been working so hard, Lucy. You deserve it."

He stepped back, a thoughtful expression on his face. "Now, I remember you mentioned your mother left you some… keys? Celestial Spirit keys, right?"

Lucy nodded, her eyes shining. "Yes, Sensei! She taught me a little about Celestial Spirit magic."

"And you mentioned they were Zodiac keys?" Rimuru asked, his otaku instincts kicking in. "How many did she leave you?"

The mention of her mother brought a flicker of pain to Lucy's eyes, quickly replaced by a steely determination. "Yes, Sensei. They're Zodiac keys. I remember… Aquarius… and…" She rummaged through her bag, pulling out a small, ornate box. "Here they are!"

She opened the box, revealing two golden keys. "Aquarius and… Capricorn!"

Rimuru's eyes widened. "Capricorn too? That's amazing!" He paused, his expression turning serious. "Lucy, I know you are training for revenge. But, I also want to help you master your magic. Celestial Spirit magic is powerful, and you have a natural talent for it."

Lucy's eyes flickered, a mix of determination and sadness swirling within them. "Yes, Sensei. I won't forget why I'm training."

Alright, let's crank up the power level and add some godly flair, Mashima-style!

"Wait, Lucy! Hold on a sec!" Rimuru exclaimed, snatching the keys from her outstretched hand. "Let me take a look at these."

He held the golden keys up to the light, his eyes glowing with analytical power. "Ciel, analyze these keys! Can I replicate them? And more importantly, can I make them stronger? Like, Celestial Spirit King level, or even beyond!"

"Analysis complete," Ciel's voice echoed in his mind. "Replication is possible. Enhancement is also achievable. I suggest incorporating materials with high magical conductivity and infusing them with divine energy."

"Perfect!" Rimuru grinned. "Ciel, start crafting two new keys. I'm thinking… Norse mythology inspired! A sun and moon pair, male and female! Make them ridiculously powerful!"

"Understood," Ciel replied. "Crafting process initiated."

A moment later, two new keys materialized in Rimuru's hand. One was a brilliant gold, radiating warmth, the other a shimmering silver, cool and serene.

"Alright, Lucy! Check these out!" Rimuru said, handing her the new keys. "These are special birthday presents! Made just for you!"

"Wow, Sensei! They're beautiful!" Lucy gasped, her eyes wide with wonder. "What are they?"

"These are the keys to Sol and Luna," Rimuru explained, "the Sun and Moon Spirits! They're… well, let's just say they're a bit stronger than your average Celestial Spirit."

"A bit?" Lucy asked, tilting her head.

"Think… god-level powerful!" Rimuru grinned. "Now, give them a try! Summon them!"

Lucy, her eyes sparkling with excitement, held up the golden key. "Open, Gate of the Sun, Sol!"

A blinding flash of light filled the clearing, and a figure materialized before them. He was tall and muscular, with golden hair that shimmered like sunlight. His eyes burned with a fierce, radiant energy. He wore armor made of pure light, and his presence radiated warmth and power.

"Lucy-sama," Sol said, bowing respectfully. "It is an honor to serve you."

Next, Lucy held up the silver key. "Open, Gate of the Moon, Luna!"

A soft, silvery light filled the air, and a figure materialized beside Sol. She was graceful and ethereal, with long, flowing silver hair. Her eyes shimmered like moonlight, and she wore a gown woven from starlight. Her presence radiated a cool, calming energy.

"Lucy-sama," Luna said, her voice soft and melodic. "I am at your service."

"Wow…" Lucy breathed, her eyes wide with awe. "They're amazing!"

"They are indeed," Rimuru said, a proud smile on his face. "Now, Lucy, I want you to remember that these keys represent more than just power. They represent the balance of light and darkness, the strength within you."

"Yes, Sensei," Lucy said, her voice filled with determination.

"Alright, that's enough for now. De-summon them Lucy." Rimuru said.

Lucy nodded, and with a gentle wave of her hand, Sol and Luna vanished, leaving behind a faint shimmer of light. She carefully placed the golden and silver keys in her box, alongside Aquarius and Capricorn.

"Thank you, Sensei," Lucy said, her eyes filled with gratitude. "This is the best birthday ever!"

"You're welcome, Lucy," Rimuru said, patting her shoulder. "Now, how about we get back to training? You're nine now, and we've got a lot to cover."

Lucy's eyes lit up. "Yes, Sensei!"

"Alright, Lucy, let's get started!" Rimuru announced, clapping his hands together. "Today, we're focusing on endurance and raw power!"

"Yes, Sensei," Lucy replied, her voice steady, picking up her training sword.

"First up, warm-ups!" Rimuru shouted, "1000 push-ups, 1000 sit-ups, 1000 squats, a 10-mile run, followed by two hours of pure strength training! Got it?"

Lucy's eyes narrowed, a cold determination settling over her features. "Yes, Sensei."

Rimuru blinked, his jaw dropping slightly. Wait, did I just say 1000 of everything? And she's not even flinching? He thought. This kid is insane!

"Alright, then! Let's go!" Rimuru yelled, trying to match her enthusiasm, though he was secretly wondering if he'd gone a bit overboard.

Lucy started her routine, her movements precise and powerful. Push-ups, sit-ups, squats – each rep was executed with flawless form and unwavering speed. Rimuru watched, his eyes wide with disbelief.

She's doing it! She's actually doing it! 1000 of everything! And she's not even breaking a sweat! he thought, his mind reeling. This is beyond human! This is beyond anything I've ever seen!

As Lucy finished her run, her breath barely even ragged, she turned to Rimuru, her eyes cold and focused.

"Strength training, Sensei?" she asked, her voice devoid of emotion.

"Uh, yeah, sure," Rimuru stammered, still trying to process what he'd just witnessed.

Lucy began her strength training, lifting weights that would have crushed most adults. Her muscles bulged, but her face remained impassive.

"Lucy," Rimuru asked, his voice laced with concern, "why are you pushing yourself so hard?"

Lucy stopped, her eyes turning to him, cold and hard. "I remember it every day, Sensei. Every single moment."

"Remember what?" Rimuru asked, his voice soft.

"I remember how my parents were tortured," Lucy said, her voice a low growl. "I remember how they died in front of me. I remember every single detail. And I will kill them all. Every. Single. Day."

Rimuru's eyes widened. He saw the raw, unadulterated rage burning within her, a fire fueled by grief and a thirst for vengeance.

She's not just training for strength, he thought, his heart sinking. She's training to become a weapon. A weapon of pure, unadulterated revenge.

He placed a hand on her shoulder, his voice gentle. "Lucy, I understand your pain. But revenge… it can consume you."

Lucy shrugged off his hand, her eyes still cold. "It's all I have, Sensei. It's all I want."

Rimuru sighed, knowing he couldn't change her mind. "Alright, Lucy," he said, his voice firm. "But remember, strength isn't just about killing. It's about protecting. It's about making sure no one else suffers like you did."

Lucy nodded, her eyes still hard. "I understand, Sensei.''