The afternoon light streamed through the cracks in the warehouse roof, scattering into drifting specks of dust that danced in the air.
Yuuto stood in the center of the room, still holding his flip phone — through it, Lady Avalon's graceful face appeared, smiling sweetly yet clearly hiding a teasing intent.
"Alright, Yuuto," she began, her voice soft but filled with the authority of someone who had lived for centuries.
"Your next lesson is one of the most essential foundations every magus must master — Bounded Field."
"Bounded Field?" Yuuto repeated, frowning slightly.
"Yes," Lady Avalon replied casually, her silver hair glimmering.
"It's a form of magecraft that allows you to create a limited space — a closed area where you define your own laws of magic.
That way, you can practice without worrying about being seen or affecting ordinary humans."
Yuuto nodded slowly. "So, it's like a private domain that hides a magus's work?"
"Exactly!" Lady Avalon smiled proudly, like a teacher delighted that her student answered correctly.
"But unfortunately… Arthur, in his lifetime, never really studied Bounded Fields.
He spent more time swinging swords than writing magical formulas."
Yuuto raised an eyebrow. "So that means this is going to be difficult, huh?"
"For you? Hmm… not really," Merlin rested her chin on her hand, her tone turning playful.
"But generally speaking — for a beginner with no magical lineage, it takes one to three months.
For descendants of magus families with Crests, around one to two weeks.
A prodigy from the Tohsaka family? Three to seven days.
And an experienced magus… a few hours, maybe."
Yuuto rubbed his temples. "Okay, so which category am I?"
"Of course, you're special~" Lady Avalon replied immediately, her eyes sparkling mischievously.
"You have the body of Arthur Pendragon, complete with a Dragon Core and Dragon Factor, plus the battle instincts of a true king.
And most importantly…" — she tapped her chest proudly — "you have me, the greatest teacher in all dimensions!"
Yuuto stared flatly at the hologram. "So… how long?"
Merlin pretended to choke on air. "So rude, Yuuto-san! Can't you at least let me brag a little? I'm going to cry, you know!"
Her expression was exaggeratedly sad, though her violet eyes glimmered with suppressed laughter.
"Sensei…" Yuuto's tone was flat, but clearly resigned.
Merlin waved her hand dismissively. "Alright, alright. With your body and my guidance, it should take around…"
She looked at her crystal screen, then smiled with satisfaction.
"Three to seven days. No more."
Yuuto let out a long sigh. "So I'm in the genius class, huh?"
"Well, that's because Arthur himself didn't study magecraft much," she said nonchalantly. "He mastered many things… but magic wasn't one of them."
A brief silence lingered.
"Alright," Lady Avalon said finally, her tone returning to that of a teacher.
"Let's begin your first Bounded Field lesson. Focus, Yuuto — this is where you'll learn to write small laws for the world itself."
Yuuto looked around the empty space and nodded.
"Understood, Sensei," he said quietly but firmly. "Teach me… how to create my own world."
"Since you've already mastered controlling the flow of mana within your body," Lady Avalon's voice echoed gently, laced with the commanding calm of a mentor,
"we can move on to the next step — Formula Composition."
Yuuto stood tall in the center of the warehouse, still holding his flip phone.
The soft glow from its screen lit his focused expression, while the air around him faintly trembled with mana residue.
"Formula Composition?" Yuuto repeated softly.
"Correct," Lady Avalon replied, crossing her arms elegantly.
"Every form of magecraft we create is the result of rewriting small laws of the world."
Her tone flowed like a chant — every word carried ancient weight.
"A formula," she continued, "is the fundamental language of magic — sentences written with mana to command the world to do as you wish.
Without a formula, magic is nothing but wild, formless energy."
Then, with a sly grin, she added,
"Think of it like a poem — but if you read it wrong, you might blow up your house."
Yuuto grimaced. "That doesn't sound encouraging."
"Of course not," Merlin said cheerfully. "Now, listen carefully.
To build a Bounded Field, you must write a formula with three core components:
First — spatial coordinates, the location where your new laws will be applied.
Second — basic rules, which define the field's purpose.
And third — mana stabilization, to prevent the field from collapsing under pressure."
Yuuto listened intently.
The golden light of his Dragon Core pulsed faintly beneath his skin, as though resonating with her words.
"The first formula we'll learn," Lady Avalon continued calmly, "is the simplest boundary — Isolation.
It forms a silent domain — a space where sound, light, and movement from outside cannot enter.
That is the foundation of the Bounded Field."
Yuuto nodded slowly. "So, I have to write my own law… with mana."
"Exactly, my student," Lady Avalon said, her smile gentle yet proud.
"Alright," her voice came again from the phone, light but firm, "to help you understand faster, I'll send a direct demonstration video of the Formula Composition process.
That way, you can see how a true magus writes the world's small laws."
Before Yuuto could respond, the call ended.
Her voice vanished, replaced by the faint hum of the warehouse's old ventilation.
A few seconds later—
Ding.
Yuuto's phone vibrated softly.
He looked at the small screen, reading the new notification:
[File Received: Avalon_Sample_Formula.mov]
"So this is the video she mentioned…" Yuuto murmured, pressing play.
---
A soft silver-blue glow filled the tiny screen.
In the video, Lady Avalon stood gracefully in the center of a magic circle, its intricate runes glowing as if carved from light itself.
Her gown flowed gently with the circulating mana — a wind that belonged only to the world of magic.
"First," Merlin's calm voice narrated, "feel the breath of the world.
Don't force mana to move — let it flow with you."
She slowly raised her hand.
Around her, shining symbols began to form — ancient magical letters arranged like a constellation.
Each glowing line was not just an image, but a living equation — a fragment of command inscribed into reality.
"Next," she continued, "define the boundaries of your space according to your will.
The world will listen… if you know how to speak to it."
The air around Merlin trembled softly.
Light from her circle reflected off her silver hair, and slowly, the space around her turned perfectly still — no sound, no motion, as if time itself had paused for her.
[Formula Composition: Isolation Field — Success.]
---
Yuuto stared at the screen for a long time, entranced.
"It's… beautiful," he whispered.
Not just because of Merlin's grace — but because the magic itself lived; it wasn't just technique, it was art.
He closed the phone slowly and took a deep breath.
"Alright. My turn."
He raised his right hand, recalling Merlin's movements from the video — the way her fingers traced lines in the air, the slight turn of her wrist, the gentle breath before writing the formula.
A faint light appeared at his fingertips, unstable but real.
He began to speak softly — not a chant, but a structured line of magical syntax, just as Lady Avalon had taught.
One by one, small glowing symbols appeared in the air — not yet connected, flickering faintly.
The energy from his Dragon Core stirred, restless, like a dragon eager to shape the world with him.
"Come on…" Yuuto whispered, his focus unwavering.
"If she could do it gently, so can I."
And thus, Yuuto's second training began — guided by Merlin's unseen presence.
Minutes turned into hours.
By nightfall, the light thickened, forming faint patterns on the cracked floor.
The air in the warehouse grew still, heavy with quiet energy.
Yuuto gazed at his work in awe.
"So this is… the first step to writing a world."