The building stood deep within a dense forest. Despite being surrounded by massive trees that seemed to pierce the heavens, soft sunlight bathed the structure. Inside, there was no sign of life, nor even the lingering presence of any creature. Curiously, however, the floors were spotless, maintained in an impeccably clean state without a single speck of dust.
In a room within this building, Reiji—no, the person formerly known as Reiji Saiki—opened his eyes.
"Where on earth am I?"
He pressed a hand to his forehead, scanning his surroundings. After a few seconds of thought, he nodded as if everything had suddenly clicked.
"Right. I fused with that Light Sphere... I see. It really was a fusion. The knowledge is there, and my consciousness is definitely still my own. No mistake about it."
As Reiji looked around, he finally realized he had been lying in a bed. A magic circle was inscribed on the floor beneath it, leading him to guess that some form of magic had been sustained on his body until the moment he woke. He dressed in the clothes placed by the bedside and stood up.
"So, this new body... what do I actually look like?"
The Light Sphere’s knowledge identified him as Zephyle Zond. Following that memory, Reiji found a basin of water Zephyle had prepared and peered at his reflection.
The face of a boy with crimson hair stared back at him. His features were handsome and well-defined. His eyes were a striking blue, creating a vivid contrast against his red hair. He stood about 165 centimeters tall, appearing to be around fifteen years old. Since Reiji had been seventeen in his previous life, he had effectively rejuvenated by two years.
"According to Zephyle’s knowledge, though, this body is pretty outrageous."
The information stored in his mind revealed that this vessel was something Zephyle and his clan had crafted using the absolute pinnacle of their mana and technology. Because the clan had eventually died out due to old age, they had treated this body to be unaging—provided the user possessed a certain level of mana.
The catch was that while he was unaging, he was not immortal. Even a gathering of the world's greatest mages had failed to grasp humanity's ultimate dream of eternal life. In its place, however, the body possessed incredible regenerative powers and high-performance physical capabilities.
"Well, that’ll do for now."
After processing the specifics of his physical vessel, Reiji poured water from a pitcher on the table into a wooden cup and drained it. As the water hit his throat, a thought occurred to him.
"Wait, is this water hundreds of years old too?"
He poured another cup and stared at the clear liquid. If Zephyle's claims were true, he had become a Light Sphere and retreated into a Mental World within the Gap Between Worlds centuries ago to find a successor for Beast Magic. Naturally, this body, the water, the bed, and the clothes must have been prepared before Zephyle discarded his physical form. Considering everything remained perfectly fresh, Reiji began to truly appreciate the sheer scale of power held by a clan of world-class mages.
The water was so crisp it tasted as if it had been drawn from a mountain spring only moments ago. Having grown up in a rural town in Tohoku, Reiji considered himself a judge of good water, but this was on an entirely different level. It was so delicious that he drank several more cups before finally setting the cup down.
"I should probably take a look around."
While he had a general layout of the building thanks to Zephyle, those were someone else's memories. He needed to see it for himself.
The bedroom contained only the bed, a table, a chair, and the water set.
"Hm? What’s this?"
His eyes caught a painting hanging on the wall. It depicted twelve people of various ages and genders.
These were the masters of Earth Magic, Water Magic, Wind Magic, Light Magic, Dark Magic, Space-Time Magic, Space Magic, Summoning Magic, Alchemy, Arithmetic Magic, and Ancient Magic—all led by Zephyle, the master of Fire Magic. Zephyle’s knowledge told him that this group was a clan once said to be capable of toppling a nation in a matter of hours.
However, something else about the painting gripped Reiji's attention. One of the figures—the practitioner of Arithmetic Magic—was wearing a black school uniform, the kind worn by Japanese students. Furthermore, the man had the black hair and black eyes characteristic of a Japanese person. Reiji dug deeper into his inherited memories.
"Takumu Suzunose. An Arithmetician. He was definitely from home."
The memories confirmed that Takumu Suzunose had been unaging. Reiji’s current body had been modeled after Takumu’s physical traits and then further enhanced.
"Does that mean there are other Japanese people in this world besides me and Takumu?"
He pondered the possibility for a moment before shaking his head. Even if there were, he was no longer Japanese in a physical sense, regardless of his soul. At best, they could share some nostalgic stories.
"If he was unaging, though, how did he die?"
He searched his mind for the answer. It turned out Takumu had been caught in a power struggle between major nations and was poisoned. Though he had managed to flee back to Zephyle and the others, they couldn't synthesize an antidote in time.
"I guess that’s what happens when you get tangled up with the nobility in a world like this."
Takumu’s Arithmetic Magic had been a unique, original art that only he could use. It allowed him to quantify and analyze targets, though it wasn't particularly suited for direct combat.
"I get it. It was like Appraisal or Analyze in a video game."
While it was a completely unknown concept in this world, Reiji, a lover of subcultures, understood it perfectly.
"Alright, that’s enough for this room. Next is the laboratory."
Walking barefoot across the floor, he opened the bedroom door. The mansion was likely being maintained by some form of magic, as the hallways were free of even a speck of dust.
"I see... they used Space-Time Magic to halt time within the mansion."
He followed his inherited knowledge down the hallway. The mansion was relatively small, as Zephyle had used it as a solitary base while searching for a successor after his clan had passed. Reiji reached the laboratory in just a few minutes.
A plaque hung on the laboratory door: "Cursed be any who open this door without the aptitude for Beast Magic."
"Well, at least I can read the local script now," he muttered.
According to his memories, anyone without sufficient mana to inherit Beast Magic would be incinerated by a hellish inferno the moment they tried to open the door.
"Talk about extreme security."
He joked to mask his nerves as he reached for the doorknob. Even with Zephyle’s internal "seal of approval," the thought of being roasted alive made him cautious. However, the door clicked open with startling ease.
"Phew."
He let out a breath of relief and stepped inside.
The laboratory was much larger than the bedroom, roughly the size of a thirty-tatami room. A massive magic circle occupied the back half of the space. The front half, which likely once held experimental equipment and reference books, was now mostly empty. However, a single, exquisite jewelry box sat on a table near the magic circle.
"That’s a fancy box. Let’s see what’s inside."
He approached and lifted the lid.
"A bracelet?"
He pulled out a ring about ten centimeters in diameter. It was clearly intended to be worn on the wrist. At a glance, the jewelry box—with its fine carvings and inlaid gems—seemed far more valuable than the simple ring.
He felt a nagging sense of incongruity. Why keep a seemingly plain bracelet in such an expensive box? It didn't add up. Reiji consulted Zephyle’s knowledge once more.
"I see. This is worth more than a billion jewels."
The bracelet was a form of item storage called the Misty Ring. It was a masterpiece created by the clan's greatest space magician, Lizy Flow, and their top alchemist, Estha Nor, with help from Takumu the Arithmetician. Zephyle had mentioned a collection of magic tools and rare materials; they were all stored inside this ring. He wondered why it was called a "ring" when it was clearly a bracelet, but he chalked it up to the creators' whims.
With a smirk, Reiji placed the Misty Ring back in the box and walked toward the magic circle at the rear of the laboratory.
"So this is for Beast Magic."
Reiji already understood the nature of the art through his inherited memories. By chanting an incantation at the center of the circle, the ritual would drain mana from the practitioner to create a Beast. The resulting creature was determined by a complex mix of the user's mana, personality, psyche, and preferences; it couldn't be chosen at will.
If that were all, it wouldn't be the clan's ultimate secret. The true power of a creature created through Beast Magic lay in its evolution. By consuming the Magic Stones found inside Monsters, the Beast could grow stronger, faster, and more formidable. Its path of evolution was entirely dependent on the stones it ate, offering infinite possibilities. Theoretically, there was no limit to how strong a Beast could become, though no one had ever reached that theoretical ceiling.
In short, Beast Magic was an art where the mage and the Beast grew together.
However, the mana requirement was so staggering that an ordinary mage would have their very life force sucked dry, and the resulting impurities would cause the ritual to fail.
Reiji took a deep breath and stepped onto the circle.
"I made a promise to Zephyle, but more than that, I’m genuinely interested in this. No harm in trying. Then again, I used to be a lot more cautious... is this also the fusion talking?"
Perhaps this was the change Zephyle had mentioned. Reiji pushed the thought aside, focused his mind, and began to speak. He knew the activation incantation by heart.
"I am the one who brings forth the beast with my mana. I am the one who lives alongside the beast. Devour my mana and manifest the beast sleeping within me into this world. Live with me, die with me. Show yourself!"
An incantation was, essentially, the act of weaving mana into spoken words. Though it normally took years to master, Reiji performed it flawlessly. He poured an ocean of mana into the words—a quantity that would have shocked even Zephyle, the world's greatest mage.
The magic circle beneath his feet erupted in light, the radiance growing more intense by the second as it gorged itself on Reiji's mana. Even with his vast reserves, the cost was immense. Five minutes passed, then ten, then twenty.
"Guh...!"
As he neared his limit, his knee hit the floor. The magic circle flared with a final, blinding brilliance before the light abruptly vanished.
"Did... did I do it?"
Drained and on the verge of collapse, Reiji peered through his hazy vision. He saw a glossy, jet-black cocoon. As the cocoon began to crack and shatter, his consciousness started to fade into the dark. In the final moment before he passed out, he felt something warm and fluffy, heard a soft, pampered growl, and caught the sound of something clattering onto the floor.