Low-Fantasy Occultist Isekai

Nick's body protested as he sat up, sore from the previous day's exertions. For a brief moment, he allowed himself to sit in silence, taking slow, deliberate breaths. The air seemed lighter now, more responsive. His newfound sense itched at the back of his mind, allowing him to vaguely make out two bodies moving just below his room.

That'd be Mom and Devon, I suppose. I didn't pay enough attention to notice yesterday, but having a sense for every displacement of air around me is basically like having Hoplite's Help on all the time. Well, it's a bit vaguer, but I'm sure I can fine-tune it.

Nick took his time getting dressed, not ready for an ordinary conversation yet. His brother's departure loomed, and the entire family was caught up in preparations. His mother's voice carried faintly through the walls, urging Devon to hurry up. The busyness was a blessing; it gave Nick the space to think.

He rubbed his face, letting everything he had been too tired to consider wash over him. The ritual, the fight, and the lives he'd taken felt distant, like a story someone else had lived. Yet, it was undeniably his.

Killing two men had been necessary. They'd been a threat to him and, worse, to the girls. There had been no hesitation in his actions, no moment of doubt. And that, more than anything, was what troubled him.

Back on Earth, he had faced life-and-death situations before. As an occultist, he often fought other practitioners to keep hold of his few resources. The times he failed still stung, though he always told himself he had done his best. Killing had been an option, but it wasn't something he did lightly, as it often only meant running from his opponent's faction. But yesterday, it had been his first instinct.

Why was it so easy?

Nick leaned against his small desk, allowing his new sense to fill his mind with information. Motes of dust drifted aimlessly while insects he would have never noticed scurried about.

Was this new power worth the life of two men? While it hadn't felt wrong at the time, the lack of remorse gnawed at him. What would old Nick have thought?

I'd like to think he would have been horrified, but I can't be sure. There seems to be a barrier between us that makes it hard for me to act as who I used to be. It sure doesn't come from kid Nick.

"Maybe something did change during the reincarnation," he muttered, running a hand through his hair. "Or maybe it's just this place. Everything is different here."

The memory of Old Ogden's warning surfaced. The old man had told him how the system could shape not just abilities but also a person's essence. Was the cold efficiency he'd displayed a side effect of his Class? Or had the new abilities he wielded done something to him?

Nick clenched his fists. He didn't have answers but wouldn't let himself slide into a mindset where life held no value. He would keep an eye on his thoughts and his actions. If this world demanded a harder edge, he would give it—but not at the expense of who he was.

Pushing the moral quandary aside, Nick focused on more practical matters. He sat cross-legged on the floor, summoning his status screen.

"Not bad," Nick murmured, scanning the screen. The addition of wind affinity and the stalking gait were the most significant changes. While they weren't particularly powerful yet, he was sure they would prove invaluable.

His lips quirked as he considered the implications. Air was a versatile element, excellent for utility and mobility. While it lacked the raw destructive power of fire or the defensive capabilities of earth, it could fill in gaps his Class otherwise left open. The Stalking Gait, too, was a game-changer. Not only did it enhance his physical attributes temporarily, but it also accelerated his mana recovery, giving him a crucial edge in prolonged engagements.

"I'm finally catching up to my goals," he said, satisfied for once. The days of struggling to balance his fragile mage's body with practical combat skills were coming to an end.

Still, the continued presence of the wind affinity in his status forced him to reevaluate his assumptions. He hadn't even known it was possible to grant himself new traits, but now that he thought about it, he did get [Blasphemy] because of his reincarnation, which meant specific experiences could unlock new ones. He just needed to understand why the affinity was permanent.

The way I see it, the main culprit is the human sacrifice. That is the only significant difference between this and the [Welcoming of the Sun]. Now, to get a bloodline ability on Earth, I would have had to sacrifice an entire town, and even that would have been likely to fail. The difference, of course, is that people here constantly interact with mana. Even bandits such as those two had enough power to be considered great mages back then…

The possibilities were endless, but Nick couldn't afford to chase every thread. He needed a plan—a long-term strategy that accounted for both his growth and the mysteries surrounding the System.

Picking up a stylus and parchment, Nick wrote down his objectives into short-term and long-term goals in English. There was no need to be sloppy, even if he intended to burn the paper after sorting his thoughts.

Short-term:

1. Refine Stalking Gait: It is functional, but I need to master it until it becomes second nature.

2. Continue developing my existing repertoire. I need to use what I have without excessively cluttering my spell list.

3. Experiment with Air Affinity: Understanding the limits of this new power will allow me to integrate it seamlessly into my combat style. This is probably where most of my new spells will come from

Long-term:

1. Understand the System's anomalies: The inconsistencies between Earth's rituals and this world's need to be resolved.

2. Continue learning from Roberta's diary: it is the single greatest piece of magic in my vicinity and it would be foolish to leave it be because it's not perfectly compatible with me.

3. Prepare for Dungeons: while Arthur is investigating the issue, I already know there are significant fluctuations within the Green Ocean. It is just a matter of time before it reaches the breaking point.

Nick's musings were interrupted by the sound of steps outside his room and the smell of breakfast wafting through the house. His stomach growled, reminding him that reflection and planning were best done on a full stomach.

After disposing of the paper, he left his room and found Devon emptying a pack while their mother lectured him about the importance of bringing cleaning supplies, not just food and weapons. The sight brought a smile to Nick's face, and he allowed his worries to fade for a moment.

"Don't forget to eat today," Elena chided, spotting him lingering at the doorway.

Nick smiled. "No worries, I'll leave nothing for Devon."

"Hey!"

By the time Nick finished cleaning the dishes, the sun had climbed high in the sky. An unfortunate side effect of his brother's leaving was that he was so busy that he could avoid doing his chores without reprimand. Nick would have to pay him back somehow.

Sitting cross-legged in his room, surrounded by scraps of parchment and half-written notes, he stared at his most prized possession. The worn leather cover, etched with a symbol he still hadn't deciphered, almost seemed aware of his gaze. He knew it was the secrecy spell at work, but it didn't make it less weird.

Roberta's diary was unlike anything he'd encountered in his two lives. It didn't just outline magical theories; it lived them. The pages adjusted the flow of their text depending on the reader's understanding. It was maddening, beautiful, and utterly compelling.

He flipped it open, careful not to linger on the more dangerous-looking diagrams. Even glancing at some of the more advanced symbols had left him dizzy on earlier attempts. Today, he focused on a particular section he had been puzzling over for weeks—a treatise on mana harmonics.

Mana harmonics, or Advanced Sympathetic Magic as he knew it, were the underpinning of her unparalleled magical feats. By aligning the frequency of her mana with natural energies, she could amplify her spells to levels that defied logic. The implications were staggering, but Nick quickly realized there was a reason no one else had followed in her footsteps. It was hard.

His mana flow was much easier to tame than most others, thanks to Parsimonia, and yet he could barely understand what she was talking about. Many techniques were out of his reach without the proper affinity. He hoped that could change now that he had one of his own, despite the principles being based upon a different element.

He traced the swirling diagrams with his finger, feeling a faint resonance through the page. It was as though the diary itself encouraged him to try again.

Nick inhaled deeply, beginning the breathing pattern of the Stalking Gait to steady his mana circulation. He let his awareness expand, reaching out to the ambient air mana around him.

I'm still not there, but I think I understand what I almost did yesterday. In a way, I was trying to harmonize with the air all around me.

But as he delved deeper, Nick began to see why Roberta's methods were so dangerous. Her approach required breaking down the barriers between internal and external mana, creating an almost symbiotic flow. It was elegant but reckless. A single misstep could destabilize the entire system, leaving the practitioner vulnerable to a backlash.

He pulled back, beads of sweat forming on his brow. "Not yet," he muttered, closing the diary with a sigh. "I'm not ready for this part."

Still, he couldn't help but feel exhilarated. Even if he couldn't replicate Roberta's techniques perfectly, he was learning. Every hour spent with the diary expanded his understanding of magic in ways no self-training ever could.

I'm guessing she must have had at least a Greater Affinity. Higher, if that's possible. I should probably avoid pushing until I'm at Intermediate, but even this exercise is enough to give me new insights.

It would take some time before Nick was ready to turn those into something practical, but it made him feel good to advance his understanding, even just a little bit.

Setting the diary aside, Nick returned to the other great mystery that afflicted him.

The ritual's effects were undeniable—a permanent affinity achieved with relatively modest resources. If it could be repeated, it would open doors to possibilities he hadn't dared to dream of. But he needed more control over his new affinity to understand the process. Unless he knew exactly what having the Trait was doing to his mana, he couldn't hope to replicate it.

That meant spells.

Unfortunately, his repertoire was limited. While his Class granted access to esoteric abilities, it lacked the elemental versatility he now craved. Developing his own air-based spells would take weeks, months, and possibly years if he wanted to bring them to high proficiency, and he didn't have that kind of time.

One alternative was to ask Vicar Alexander for help, as he was the only man in town with the connections to grant him the knowledge. However, Nick immediately dismissed the idea. The man's interest in him was already suspicious, and he wasn't ready to owe the temple anything more than he already might. That left one option: trying his luck with the town's shops.

Now that the cat's out of the bag that I can use magic, I no longer have a reason to avoid them. Might as well take a look.

Nick shrugged on his cloak, securing his coin pouch tightly. Floria wasn't exactly known for its magical goods, but adventurers passed through often enough that the occasional treasure found its way onto the shelves. He knew most of the spellbooks would be secondhand, incomplete, or outright dangerous, but he hoped he might find a gem in the rough.

The walk to town was brisk and uneventful. The streets bustled with activity as the villagers went about their business.

The first shop he entered was a small, cluttered place tucked into a narrow alley. Its wooden sign, claiming it to be "The Finest Grimoire Shop," was painted with the image of an open book and creaked faintly in the wind. Inside, he was hit with the scent of old parchment and ink. Shelves lined the walls, crammed with tomes, scrolls, and the occasional odd trinket.

"Ah, Floria's newest mage has finally come to visit me, has he? Got bored with the temple's fare?" The shopkeeper asked. He was a wiry man with spectacles perched precariously on his nose, looking up from his ledger. "Looking for something specific, or just browsing?"

"Spellbooks," Nick replied boldly, feeling good about not needing to be secretive anymore, and stepped between the precariously stacked piles of books. "Preferably something to do with air magic."

The shopkeeper snorted. "Air magic? That's a rare request. Most folks want fire—something flashy to scare off monsters. But let me see what I've got."

Nick waited as the man rummaged through a chest behind the counter. After a few minutes, he emerged with three slim volumes.

"Not much," the shopkeeper admitted, laying them out on the counter. "But it's what I've got. First one's a basic primer on elemental manipulation—not specific to air, but it might help if you are just starting out. Second's an old spellbook from some adventurer. There should be a few wind spells in there, though it's missing half its pages. The last one's… well, it's a gamble. No title and no author, but it's got some strange diagrams that might be what you're looking for. Might even be a treasure, eh?"

Nick considered his options. The first book was too basic to be useful, and the third one was intriguing, but he couldn't feel anything special about it and suspected it was a scam. He picked up the second book, flipping through its weathered pages. Despite the gaps, it had several promising entries.

"How much for this one?" Nick asked.

"Three silvers." The shopkeeper grinned.

Nick winced, but he handed over the coins without complaint. Knowledge was worth the expense.