Chapter 4:Magic

Rimuru exhaled, his gaze lingering on Lucy as she stood before him, her expression unyielding. He had just finished speaking, his words hanging in the air. "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."

A heavy silence settled between them, the weight of her words and his concern hanging in the air. He had watched her surpass every expectation he set for her—no, he had shattered them. What took seasoned warriors years, she accomplished in mere months. But there was still something missing. 

"Lucy, put the sword down," Rimuru instructed, his voice calm but firm, breaking the tension.

Lucy blinked in confusion but obeyed, resting the gleaming weapon against the training post. Her fingers flexed, as if already itching to reclaim the hilt. "What is it, Sensei?"

Rimuru crossed his arms, studying her. "You've mastered my swordsmanship, martial arts, and combat tactics. But strength isn't just about weapons."

Lucy frowned, her mind already racing ahead. "You mean magic?"

Rimuru nodded. "Exactly. And not just Celestial Spirit Magic. You barely use your keys, Lucy. They're powerful, but I don't want you to rely on them too much. A true warrior doesn't depend on anything but themselves. That's why I've been waiting to teach you this."

Lucy's eyes gleamed with curiosity. A hunger, a relentless drive burned behind them. "Then teach me, Sensei. I'll master it. Just like everything else."

Rimuru smirked. "I was waiting for you to say that. But let's see if you can handle this first."

With a flick of his wrist, dark flames crackling with violet lightning flared to life in his palm. The sheer pressure of the magic distorted the air around them, sending a pulse of energy rippling through the clearing. The grass beneath them withered, scorched from the intensity alone.

"This is Black-Flame Thunder," Rimuru declared, his voice carrying an ominous weight. "A fusion of fire, darkness, and lightning. It doesn't just burn—it consumes. It paralyzes, devours, and lingers like a curse. Unlike normal fire, it won't stop unless I will it."

Lucy's breath hitched. The power radiating from Rimuru was overwhelming. The flames crackled, twisting like living things, eager to be unleashed. But instead of fear, exhilaration flooded her veins.

"You're going to teach me that?" she asked, a grin tugging at her lips, her stance shifting forward in anticipation.

Rimuru chuckled. "If you can learn it. Don't get cocky just because you mastered everything else. This isn't just an attack—it's a force of nature."

Lucy clenched her fists. "Then let's get started."

Rimuru extended his hand, letting the dark flames dance in his palm. "First, focus your magic. This isn't just about controlling fire or lightning—it's about understanding destruction. Black-Flame Thunder isn't an element; it's a force beyond nature. It feeds off existence itself."

Lucy inhaled deeply, closing her eyes. She reached deep into herself, past the familiar pull of her Celestial Spirits, searching for something raw, something untamed. A spark of heat ignited in her palm, flickering wildly. It crackled, twisted, darkened—but then fizzled out.

Her fingers curled into a fist. "Tch! I can do this. I know I can."

Rimuru laughed. "Of course, you can. But not in a day. Be patient."

But patience had never been Lucy's strong suit.

Days bled into weeks, weeks into months. She trained relentlessly, every sunrise marking a new attempt, every sunset leaving her exhausted but unwilling to stop. She practiced until her limbs ached, until sweat dripped from her chin, until failure no longer stung but fueled her determination.

And then, one evening, something changed.

Standing across from Rimuru, the familiar weight of expectation settled on her shoulders. Her hands trembled—not from fatigue, but from the sheer force building within her.

"Alright," Rimuru said, his voice steady, his gaze sharp. "Show me."

Lucy exhaled slowly, raising her hand. A wisp of dark fire flickered to life, then grew, twisting and crackling with violet lightning. The energy surged around her, refined, controlled. The flames didn't just burn the air—they warped it, bending reality itself to her will.

Rimuru whistled. "Damn. You're not human, are you?"

Lucy smirked, the fire reflecting in her eyes. "You trained me, Sensei. Don't act so surprised."

"Alright, hotshot. Show me what you've created."

Lucy's fingers curled, the dark flames shifting in response. Then, with a swift downward slash of her arm, the energy condensed, coiling into a singularity.

"Abyssal Eclipse!"

Darkness imploded, swallowing the light itself. For a breathless second, all sound, all movement, all life seemed to halt. Then, the void collapsed, detonating in a controlled implosion that sent shockwaves rippling through the clearing.

Rimuru's jaw tightened. "That… That's not just magic. That's reality manipulation."

Lucy's eyes shimmered, a knowing glint within them. "And I'm just getting started."

The black flames curled around her like a living armor, weaving through the air in deadly patterns. A new name formed on her lips, a spell of her own making.

"Black-Flame Thunder: Oblivion Surge!"

The attack tore through the ground, splitting the earth itself. Rimuru barely had time to teleport away before the wave of destruction erupted, leaving a massive crater in its wake. Smoke and embers curled into the air, the remnants of her raw power.

Rimuru coughed, waving away the dust. "Alright, that one almost got me. Got any more?"

Lucy didn't respond. Instead, she lifted her hand, and the sky darkened. Celestial bodies flickered into existence, distant yet ominously present.

Rimuru coughed, waving away the dust. "Alright, that one almost got me. Got any more?"

Lucy didn't respond. Instead, she lifted her hand, and the sky darkened. Celestial bodies flickered into existence, distant yet ominously present.

"Demonic Starfall: Ragnarok Descent."

Rimuru's eyes widened. "Oh, hell no—"

A cascade of colossal, glowing stars rained down from the heavens, each pulsing with apocalyptic energy. Rimuru leaped back, barely dodging as the ground trembled beneath the sheer force of the attack.

When the dust settled, Rimuru stood there, utterly speechless. He rubbed his temples, exhaling heavily. "Lucy… remind me never to piss you off."

Lucy chuckled, twirling her fingers as the flames flickered away. "You're the one who trained me, Sensei."

Rimuru sighed, shaking his head. "I was trying to teach you balance. Not the art of obliterating everything in existence."

Lucy grinned, stretching her arms behind her head. "Oops?"

Rimuru groaned. "I think you're ready for the next step. But for my own sanity, let's take a break before you accidentally rewrite reality."

Lucy laughed, the sound light despite the sheer power she wielded. "Sounds good to me."

Rimuru sighed, watching her, a strange mixture of pride and apprehension curling in his chest. He had created a monster. A dangerous, powerful monster.

He paused, a flicker of something unreadable in his eyes.

"But Lucy… what will you do with this power?" Rimuru asked, his voice low, as if speaking to himself.

Lucy turned to him, her eyes reflecting the fading embers of her magic. "I'll use it to make them pay, Sensei. Every last one of them."

A gust of wind swept through the clearing, carrying the scent of scorched earth and lingering magic. The moon hung heavy in the sky, casting long shadows that danced like phantoms.

To Be Continued...