Arlo flinched, cold sweat pouring down his face as his mind raced. 'H-How did she figure that out?' he wondered, struggling to maintain eye contact with the vampire girl.

"You're probably wondering how I figured that out, right?" Vielle asked, studying his expression. "Well, about that, I would like to apologize. I've actually been spying on you for a while now... today and a few weeks ago when we first met."

Arlo face-palmed himself, a sigh escaping his lips. 

'She was spying on me, and I didn't even notice...' he thought. ' That aside, A few weeks ago? So that's how long it's been since I last came to this world? It's been less than a day in the other world for me, yet a few weeks have passed here.' 

It was just as he had previously concluded. The flow of time in this world was far faster than that of his old world.

"And well... when I was spying on you, I overheard you mention a world transportation spell," Vielle continued, her grip tightening on her staff as she stared at him intently. "Honestly, I've never heard of a spell like that before. So, I wanted to ask if you could tell me about it in exchange for helping you develop a Mana Core..."

'That explains how she found out... What should I do? If I tell her about the chant and she shares it with others, there's a chance they could go to my world. While I don’t really care about what happens to the world itself, I don’t want to feel responsible if anything bad happens nor do I want to put the people I care about in danger so…’

Taking a deep breath, Arlo met Vielle's gaze, his voice steady and resolute. 

"I’ll forgive you for spying on me since you helped me before but sorry, I can't agree to that. I can't tell you the chant for the spell since I can't risk letting it spread to others. I'll find a different way to acquire a 'Mana Core.' Sorry for wasting your time."

As Arlo turned to leave, Vielle's hand shot out, grabbing him by the shoulder.

"Wait, you misunderstand," she said, her voice low and urgent. "I don't want to know the chant for it. Even if you told me, I doubt I'd be able to use it. The only reason you're able to cast it is because of that Grimoire you're holding."

Arlo stared at the grimoire for a moment, while it was true that Arlo could only use magic thanks to the Grimoire, what did that have to do with the fact that other people wouldn’t be able to use the spell?

"Why wouldn't you be able to use it?" he asked, his brow furrowed in confusion. "If you know the chant, shouldn't you be able to cast it?"

Vielle shook her head, her silver hair swaying with the motion. 

"It's a Divine-Class spell. Not only does it require an incredible amount of magic power to activate, but this one, in particular, seems to come with a defense mechanism. When you chanted the spell, I couldn't understand a single word. The Grimoire probably made it so that you're the only one who can use it."

Arlo glanced down at the Grimoire, his eyes widening in realization. "I'm the only one...?"

"Yeah," Vielle confirmed, her gaze intense as she stared at him. "That's why I was going to ask, in exchange for helping you develop your Mana Core... could you tell me about this other world? I just want to know what it's like there."

The intensity of her gaze was too much for Arlo to handle, and he found himself looking away as he considered her request. "If it's just that, then..."

The suspense was killing Vielle as she waited, her heart pounding loudly in her chest. She continued to gaze at Arlo, her grip tightening around her staff, causing her hands to tremble.

"Sure. I'll tell you about the other world," Arlo said.

Upon hearing his response, Vielle's expression lit up with joy, but she quickly hid it by lowering her head, using her hat to conceal her elation.

"Ahem..." She cleared her throat, attempting to act as if she wasn't overjoyed. "Looks like we have a deal. Let's get started with the explanation then." she muttered before walking over to Arlo.

Arlo nodded nervously, watching as Vielle placed her hand on the left side of his chest, directly over his heart.

"You see, a mage's Mana Core is their heart," she explained, her voice taking on a more serious tone.

"Their heart?" Arlo repeated.

"Yeah, their heart. By creating a mana ring around it, a magician can harness its power. The first tier is unlocked when a beginner creates their very first circle," she continued, her eyes focused on Arlo's chest.

Perplexed, Arlo looked down at where Vielle had placed her hand, trying to understand the concept she was explaining.

"Hmm, that's troubling," Vielle muttered, her brow furrowing as she gazed at Arlo's heart. "You have no talent at all for magic," she said, her voice tinged with concern.

"No talent?" Arlo asked, his eyes widening in surprise.

"Yes. A mage's talent can be discovered in many ways. One simple method is to check for a mana ring that develops naturally around a talented person's heart as they grow. Most people who choose the path of a mage usually have a single partially formed ring. However, you don't have even the slightest trace of one," Vielle explained.

Arlo's expression grew gloomy, his shoulders sagging as he processed the information. "So I won't be able to form a Mana Core?" he asked, his voice barely above a whisper.

"No, you can still form one, but it'll be harder than for someone with a pre-existing ring. It's not uncommon for people without innate talent to form a mana ring on their own, but it's more challenging for them, and it's also harder to progress further." Vielle said, her hand still resting on Arlo's chest.

As Arlo's spirits dampened upon hearing Vielle's explanation, she glanced up at him, a reassuring smile spreading across her face.

"Don't worry, you'll be fine. The reason it's harder for those without a partially formed ring is because they struggle to feel the flow of mana. However, anyone can feel it and form a ring under the right conditions, and you happen to meet those conditions." She pointed at the grimoire in his hand.

Arlo's brows lifted as he realized what she was implying, a glimmer of hope igniting within him.

"You've already felt the flow of mana through that book, haven't you?" Vielle continued. "Moreover, the book itself holds a vast amount of mana within it. You can use it to form your mana ring."

Arlo gazed at his grimoire, his fingers tracing the intricate patterns on its cover. Once again, the book proved to be an invaluable ally, offering assistance when he least expected it.

"Anyhow, with the explanation out of the way, let's get started," Vielle said, gesturing for Arlo to follow her.

He trailed after her, and the two made their way over to a nearby tree. Vielle sat down, crossing her legs, but with a tap of her staff on the ground, she began to levitate, her body hovering a few centimeters above the earth.

Arlo settled on the ground beside her, his curiosity piqued. "Before we start, I've been wondering—how are you able to cast spells without chanting?" he asked, his eyes fixed on Vielle's floating form.

"Oh, through chant-less invocation," Vielle explained, a smile playing at the corners of her mouth. "When you master a spell, you'll eventually be able to do it."

"Master a spell?" Arlo repeated, his mind drifting to his system's spell mastery section, which showed that the mastery increased each time he used a spell. "So, if I use a spell enough times, I'll be able to cast it without chanting?"

"Exactly," Vielle confirmed, her smile widening. "The more you master a spell, the more you'll be able to shorten the chant required to cast it. Eventually, you'll be able to cast the spell without a chant at all, and that's called chant-less invocation."

She paused for a moment, her expression growing more serious. "This is useful in many ways. For example, you can prevent other mages from stealing your spells by mastering them."

 "I see. If I can reduce the chant, even if they memorize it, they may not be able to cast the spell themselves. And if I can cast it without chanting, it would be nearly impossible for them to steal the chant."

Vielle smiled and nodded. "That's right. But the main reason to master a spell is for combat. Chanting takes time, and one second can make the difference between life and death for a mage."

Arlo placed his hand beneath his chin, his brow furrowed in contemplation. "I should probably focus on mastering an attack spell next, then," he mused.

"Indeed," Vielle agreed. "But for now, let's focus on developing your Mana Core. Afterward, I want to hear all about your world!"

"Y-Yeah, sure," Arlo responded.

With that, Vielle began to explain the process by which a magician could develop a Mana Core. Arlo listened intently, his focus unwavering as he absorbed every detail of the potentially dangerous procedure.

"Did you understand that explanation?" Vielle asked.

"Yeah, I understood everything." Arlo replied, his voice filled with determination.

"Good. Start whenever you're ready. I'm here with you, so you don't have to worry about a thing," she reassured him.

Arlo nodded, crossing his legs and closing his eyes to focus. He tightened his grip around the grimoire in his hands, the ancient tome pulsing with a steady rhythm as he remained silent.

"I'll start now..." he whispered.

Seconds passed as Arlo sat in silence, the world around him fading away as he concentrated on the task at hand. Vielle watched, her eyes fixed on his still form as a gentle breeze swept through the landscape, causing their hair and the blades of grass around them to sway in its wake.

She knew that they would likely be there for hours, but she wasn't worried about the passing time. Her focus was solely on guiding Arlo through this critical moment in his magical development.

'...Focus... Feel the mana... Draw it into your body from the grimoire,' Arlo thought to himself, his breath slow and steady as he exhaled.

As the seconds stretched on, one blending into the next, the grimoire began to tremor in Arlo's hands, its pages glowing with a brilliant light.

Whoosh~

A sudden surge of energy washed over Arlo, the flow of mana from the grimoire coursing through his body. It was a sensation, similar yet distinct from the familiar warmth of his evolution energy that emanated from his core.

The flow of mana was cool and refreshing, like a gentle stream flowing through his veins. Arlo could feel it permeating every cell of his being, his senses heightening as the magical energy spread through his body.

'This is it, keep drawing in mana from the Grimoire.' he thought, his mind crystal clear as he focused on the task at hand. 'I can feel the mana flowing into me. Now, I just need to guide it towards my heart, to form the ring that will become my Mana Core.'

Focusing on the mana channeling through him, Arlo directed it towards his heart. Just before reaching its destination, he began to carefully circulate the mana around the organ, weaving it into a ring that orbited his heart.

It was at this point that the true challenge began. Trying to connect the two ends of the ring proved to be a delicate and intricate process. However, Arlo remained patient, taking his time and refusing to rush the procedure. After a few minutes of careful manipulation, the two ends of the ring finally joined, forming a complete circle.

[You have formed your first Mana Ring!]

The notification rang out in Arlo's mind, accompanied by a surge of magical power that blasted from his body and into the surroundings. He could feel a wave of energy flowing through him, filling every fiber of his being.

Slowly, Arlo opened his eyes, his hair swaying gently as the magical power coursed through his veins. While the grimoire continued to glow in his hands, his attention was drawn to the bright blue screen that hovered before him.

[+5 Mana.]

[You have developed a 'Mana Core'.]

[New System Section Unlocked.]

[Mana Core Rank: Tier 1]

A smile grew on Arlo's face as he stared at the notification, the system confirming that he had indeed managed to awaken his Mana Core, just as he had hoped.

“My senses feel sharper...”Arlo muttered, closing his eyes once more.

With his newly developed Mana Core, Arlo could perceive the flow of mana with greater clarity. He could sense the magical energy not only from the grimoire and his own core but also from the surrounding environment.

Mana was everywhere—in the air, the ground, and the wind. It was a discovery that Arlo had never before imagined, a world filled with magical energy that he was only now beginning to comprehend.

His thoughts were interrupted, however, as Vielle spoke up, her voice filled with surprise. "This is unexpected... I was certain you'd take a few hours. I never thought you'd get it done in less than half an hour..."

Rustle. Rustle.

Arlo opened his eyes, turning to face Vielle. Her crimson eyes were wide with astonishment, her silver hair swaying gently in the breeze.

"I guess I had a good teacher," Arlo said, a nervous smile spreading across his face as he met her gaze.

Vielle blinked, a faint blush coloring her cheeks before she quickly regained her composure. "W-Well, of course, you did! But still, to form your Mana Core so quickly... You must have a natural affinity for magic, even if you didn't have a pre-existing ring."

Rising to his feet, Arlo stretched his arms above his head, feeling the magical energy thrumming through his body. 

"Natural affinity for magic, huh… I think this might be the first time I’ve ever had talent for something in my life.” Arlo muttered with a faint smile.

He then turned his attention back to the screen before him, opening his status screen.

[Arlo Axton.]

[Race: Human.]

[Core Rank: Awakened.]

[Mana Core Rank: Tier 1]

[Level 3 (190/200)]

[HP: 100/100%]

[Energy: 100/100%]

[MP: 88/100%]

[Strength: 15]

[Agility: 17]

[Stamina: 12]

[Sense: 12]

[Mana: 5]

Arlo's heart soared with joy at the sight of his increased mana value. He couldn't wait to try casting a spell without relying on the grimoire.

'With this, I've grown stronger... Even if it's only a little, Sylvia will be able to rest easy,' Arlo thought to himself, a sense of accomplishment washing over him.

"Well, congratulations," Vielle said, her gaze falling back on Arlo's chest. "I can see the ring clearly. Looks like you'll be able to use magic without the grimoire now."

To confirm this, Arlo placed his grimoire on the ground, cutting off all contact with it. As he did so, he noticed his MP suddenly increase the moment he let go of the ancient tome.

[MP: 88% -> 100%]

The reason for this, he surmised, was that while the mana reserve from the book had been drained, his own magical reserve hadn't been used.

With this realization fresh in his mind, Arlo began to chant the incantation for Ignition—the very first elementary class spell he had ever used. His expression lit up as, midway through the chant, a red magic circle appeared before his outstretched hand.

"Heed my call... Elementary Class Fire Magic: Ignition!"

[MP: 100% -> 90%]

Arlo's eyes widened at the sight of the flame that erupted from the magic circle, its flickering light dancing before him.

"T-This is..." he muttered, his smile twitching.

The flame was small, no larger than a baseball, and yet it had consumed an entire ten percent of his magic power, leaving him baffled.

"Compared to the size of the flame when I cast this spell with the grimoire, this one is much smaller..." Arlo muttered, his brows furrowed.