Re:Zero - Reincarnated on a Co-op Route

Kaoru watched the old man, open notebook ready to jot down notes, as Raigor arranged his magical wares. "Well, my boy," the old man began, in his characteristic calm voice, "before you talk about magic, you need to understand something more fundamental: the Od. It is the root of everything in this world."

Kaoru tilted his head, intrigued. "What's so special about that 'Od', what exactly is it?"

Raigor nodded with a patient smile. "The Od is your soul, the essence that keeps you alive and functioning. Think of it as a container that stores mana, that magical energy that floats in the air. Your body absorbs it through something called the Magic Gate or more commonly known as just "Gate", which acts as a filter that decides how much mana comes in and how you use it."

The old man raised his finger for emphasis. "However, here's something important for you to understand: the size of your Od only affects the amount of mana you can store and, to a lesser extent, your life expectancy. Nothing more. Some races, such as elves or certain demi-humans, have a larger Od, so they can handle more magical energy. We humans tend to have less capacity in comparison."

Kaoru was still attentive, but Raigor noticed a shadow of confusion on his face, so he leaned over and explained in more detail. "Your physical potential and a large part of your magical talent are already predetermined, beyond the size of your Od. This means that even if you can store more mana, it won't necessarily make you physically stronger or more skilled with magic. Those things are tied to your nature, not the amount of energy you can store.

"Even your appearance and personality are influenced by it. It is unique to each being and does not regenerate or change over time. What you have is what you get."

Kaoru frowned, processing the information while quickly jotting it down in his notebook. "So my Od dictates how much mana I can use, but not if I'm talented with it?"

With folded arms and narrowed eyes, Kaoru watched Raigor carefully arrange his trinkets on the market floor. The young man had come with a barrage of questions about magic, but the older man, with his characteristic calm, seemed to be taking his time deciding how to answer.

"Boy," Raigor began, "I have explained to you how the Od dictates the limits of your magical and physical abilities. But have you ever wondered if those limits are really immovable?"

Kaoru arched an eyebrow, intrigued. "I thought you said that the size of the Od cannot be changed. Now you're telling me there's a trick?"

The old man let out a light chuckle. "Not so fast. What I will tell you is not a trick or something guaranteed. Think of it as a metaphor: imagine that your body is a glass and mana is a river. By pouring mana into your glass, you can strengthen it temporarily, but that glass has a limit; it will fill up and then it can't hold any more."

Raigor paused to make sure Kaoru was following him. "Now, what if, instead of just filling the glass, you could transform it? Not just increase its size, but change its structure to make it more efficient, stronger. A more powerful current would not break the vessel; instead, the vessel itself would adapt to it."

Kaoru frowned and pondered while writing in his notebook. "Are you saying I can change my Od? Turn it into something bigger or more powerful?"

Raigor nodded slowly, though his expression became more serious. "Some mages have tried that for centuries, but the results are uncertain. Manipulating Od is risky; after all, you're playing with the essence of your soul. But... if you could find a way to combine your Od with the mana, not just fill it, but integrate it, you could redefine what it means to be strong in this world."

Kaoru, leaning against a wall in the bustling marketplace, looked at Raigor with a thoughtful frown. The recent fight with the thugs and the huge (VERY HUGE) difference compared to Elsa's overwhelming speed had left him with many doubts. With a mixture of curiosity and frustration, he finally asked:

"Raigor, how is it possible that some people here are so.... Superhuman? Is it pure magic or something else?"

Raigor smiled with his typical calm, as he adjusted one of his trinkets on the floor. "Ah, I see you've been watching. What you describe, my boy, doesn't always have to do with casting spells or summoning advanced magic. Many of those physical feats come from what is called the Flow Method. It's something that, while basic, is deeply rooted in the use of mana."

Kaoru tilted his head, intrigued. "Flow Method? I haven't heard of it before."

Raigor nodded and began to explain in a leisurely, almost pedagogical voice. "The flow method is the most basic application of mana in the body. Think of it as a constant flow of energy, an 'aura' that permeates your muscles, bones and organs. It's so basic that most people in the world use it without even knowing it. And you, if you've been in a fight, have probably activated it subconsciously as well.

"Me?" Kaoru raised a skeptical eyebrow.

Raigor nodded with a small smile. "Yes. When someone is in a stressful situation, such as combat, their body naturally channels the mana flowing through it to increase their physical abilities. However, not everyone uses it at the same level. Its effectiveness is largely tied to one's physical talent, as well as one's fighting spirit and physical training."

The old man paused, looking at Kaoru directly. "That explains why experienced martial artists and fighters seem to almost always operate with superhuman strength and speed. They have learned to consciously control the Flow Method."

"Those with exceptional control can project their aura, and anyone who feels it may experience fear, nausea, or even fainting if the aura is too overwhelming."

"Raigor smiled with a hint of mystery. "If you plan to survive in this world, learning to consciously control the Flow Method would be a good start, boy."

Kaoru soaks up all the knowledge like a sponge, quickly writing it down with a twinkle in his eye; this information is too valuable for later.

Kaoru, still shaken by everything that had happened in the previous loop, stared at Raigor, who was calmly arranging some of his trinkets and other goods. Despite the old man's calmness, there was something in his gaze that seemed to perceive more than he was saying.

"Tell me, boy, shouldn't you be hurrying about something?" Raigor broke the silence with an unexpected question.

I frowned in surprise. "How do you know?" i asked in a wary tone.

Raigor smiled, but this time there was a spark of insight in his gaze. "Call it a guess. If you didn't have anything urgent, you wouldn't have come back to me so quickly. It hasn't even been two hours since we saw each other, and here you are, desperately coming to me asking about magic. That tells me there's something else."

I hesitated for a moment. But after weighing my options, I decided to speak, albeit with some caution. "It's about someone I saw in the slums... they call her The Bowel Hunter."

Raigor raised an eyebrow at the name. Although his face remained calm, Kaoru noticed a brief flash of concern. "Ah, so that was it then... The Bowel Hunter. It's not a nickname you earn by accident." Raigor put aside the trinkets he was organizing and sat up a little straighter, as if the conversation had just become much more serious.

"That woman is a wanted criminal in the entire kingdom of Lugunica... That woman... What did you see?" asked Raigor in a tone that for the first time seemed stripped of its usual modesty.

"I saw her heading for old Rom's loot house" I say in a worried tone.

"In that case, my boy, our conversation ends here for now. You should solve this problem first," Raigor replies in a firm tone.

Then he pointed at the bag Kaoru was carrying.

"And do you remember the notebook I gave you? It's not just a piece of paper. Use it carefully and one day, you'll understand its true value. Look for the Sword Saint to help you, he is a tall red-haired man who carries the Dragon Sword and a distinctive uniform, you will know who he is when you see him. Until then, take care of yourself, boy."

"Thank you Reigor. One day I will come and thank you for everything."