The mornings on Whale Island were quiet, the kind of quiet that seemed to hold its breath before the sun rose. Renzo's feet sank into the damp soil of the forest path as he ran, air puffing white in the cold dawn. Sweat rolled down his face despite the chill. His heart beat steady, his steps matched the rhythm of the waking island.
Every morning began this way. Run until his lungs burned, stretch until his muscles felt sharp, then drill the forms Jack had taught him the day before. Punches. Footwork. Elbow strikes. Shingen-ryu forms that flowed between offense and defense.
Jack's voice cut through the air. "Too shallow. If you throw a punch without intent, you may as well be waving at your opponent."
Renzo stopped mid-combination. His fists trembled from the strain of repetition, but he straightened, glaring back. "I am throwing intent."
Jack's weathered face barely moved. He leaned on his walking stick, eyes sharp as steel despite his age. "Your body says one thing, but your spirit says another. You are hitting air. If you strike without the will to break what stands before you, you might as well not strike at all."
Renzo tightened his fists. The forest seemed to close in around them, birds quieting as if watching. He focused, drove a punch forward, this time imagining an enemy in front of him. His fist cut through the air with a sound like cloth tearing.
Jack nodded once. "Better. Remember this. Martial arts is not about movement. It is about conviction. Without it, technique is empty."
Renzo let his fists lower, panting. "Conviction, huh. Easy for you to say."
The old man chuckled. "Harder for you to live. That is why you are here."
They moved deeper into the woods, to the clearing Jack had claimed as their dojo. A ring of trees circled the space, sunlight spilling in patches across the dirt. Renzo stretched again, but Jack raised a hand.
"Sit."
Renzo blinked. "I thought we were drilling forms today."
"You will. But first, listen." Jack lowered himself to the ground with surprising ease for someone his age. "I am not here only to sharpen your fists. I am here to sharpen your flame."
Renzo sat opposite him, brushing dirt from his knees. "Flame?"
Jack drew a circle in the soil with his finger. Inside it, he made four marks: north, south, east, and west. "Shingen-ryu teaches of the Four Principles of the Flame. Ten. Zetsu. Ren. Hatsu. These are the pillars of Nen. Without them, strength burns away like dry wood."
Renzo's heart quickened. Nen. The real start. He had been waiting for this. He leaned closer, careful not to show too much excitement.
Jack pointed to the first mark. "Ten. The art of keeping your life force close, like wrapping yourself in a cloak against the wind. It protects. It nurtures. It is the beginning of awareness."
He pointed to the second. "Zetsu. The art of silence. To still your flame until it cannot be seen. To erase your presence. Dangerous if used carelessly. Essential if used wisely."
The third. "Ren. The art of expansion. To make your flame burn brighter, stronger, overwhelming those who dare approach. It requires stamina. It requires control."
The last mark. Jack's finger pressed deep into the soil. "Hatsu. The expression of your unique self. Your soul's individuality turned into power. It is also the most dangerous. Once the door is opened, there is no turning back. That is why I will not teach you Hatsu until years from now."
Renzo swallowed. He already knew pieces of this, fragments from his past life memories of watching Hunter x Hunter. But hearing it here, in this world, from a teacher who embodied it—it was different. It was alive.
Jack leaned forward. His eyes locked on Renzo's. "Do not rush this. Many fools think power comes from showing off. Nen is not a toy. If you reveal it to those unprepared, you may destroy them. Do you understand?"
Renzo hesitated. "What if they are strong enough?"
"No." Jack's voice was like a hammer. "Never assume. Do not teach. Do not reveal. A single spark can burn a forest down. Your duty as a practitioner is to guard the flame, not to spread it recklessly."
Renzo nodded slowly. Inside, a storm of thoughts brewed. He wanted to argue. He wanted to tell Jack he already knew, that he had seen this story before. But he bit his tongue. He remembered his promise to himself—his transmigration was a secret, even here.
"Fine," he said instead. "Teach me Ten first."
Jack smiled faintly. "Eager. Good. Then close your eyes."
Renzo obeyed.
"Feel your breath. Feel the warmth in your chest. That warmth is aura. Life itself. Draw it outward, but do not let it scatter. Wrap it around you, like a cloak."
Renzo inhaled slowly, exhaled. His body buzzed faintly, a tingling that spread from his stomach to his skin. It felt like stretching a muscle he had never used before. The sensation flickered, slipped away, returned again.
Jack's voice was calm. "Do not chase it. Guide it. Think of gratitude. Gratitude for this air, this body, this chance. Gratitude grounds your flame."
Gratitude. The word struck something inside Renzo. He thought of Takehi pulling him from the sea. Of meals shared, of evenings by the fire. Of Jack's patience in training him. Slowly, the buzzing steadied. Warmth spread across his skin like a blanket.
Jack opened his eyes. A glimmer of surprise flickered before he hid it. "Good. Very good. You have touched Ten."
Renzo opened his eyes, panting slightly. "That was it?"
"That was the beginning," Jack corrected. "Hold it for longer. Strengthen it. Ten is simple, but not easy. Master it, and you will not wither."
They repeated the exercise until the sun climbed high. By the end, Renzo's clothes were drenched in sweat, his body shaking from the effort of keeping his aura steady. He collapsed onto the dirt, gasping.
Jack stood, stretching his back. "Enough for today. You did well."
Renzo squinted up at him. "So… when do I learn Zetsu?"
The old man laughed. "Impatient fool. Master standing before you learn to vanish."
Renzo groaned, but despite his exhaustion, he smiled.
That evening, Renzo sat outside Takehi's home, watching the ocean turn gold with sunset. His muscles ached, his mind buzzed with Jack's words. He rubbed his arms, remembering the warmth of Ten.
Takehi walked out, setting down a bowl of rice beside him. "You train hard these days. What is driving you?"
Renzo stared at the waves. He could not answer honestly. He could not say he was chasing a destiny written in another world's story. So he forced a grin. "I just want to be strong. That is all."
Takehi studied him for a long moment, then nodded. "Strength is fine. Just do not lose yourself chasing it."
Renzo nodded silently.
Inside, he whispered to himself. I will not lose myself. I know what is coming. And I will be ready.
The sound of the waves filled the silence, the rhythm of the ocean matching the beat of his heart.
The flame within him burned a little brighter.