A flicker of surprise flashed across Don's eyes.
Because on his data panel, a new ability had appeared.
[Observation Haki (Basic Mastery): You have gained an initial sensitivity to the energies of all things.]
Just like that, he had mastered it?
It felt so effortless that Don found it hard to believe.
"Energy, huh?"
He caught on immediately to how the panel had described his Observation Haki.
"Energy? Not a bad way of putting it."
Hearing Don murmur to himself, Shimotsuki Koushirou was momentarily stunned. After a brief pause, he smiled softly.
"That's simply your own way of describing what you sensed. Whether you call it breath, or energy—it reflects your own understanding. It seems you've truly grasped it."
His tone carried a note of admiration.
From earlier conversations with his father, Koushirou had already suspected that Don might have awakened Observation Haki. But Don's performance now made it clear that he had not only awakened it, but already begun to perceive its flow.
The speed at which he learned was enough to make anyone break into a cold sweat.
Even Koushirou himself had needed to start from swordsmanship, to slowly sense the "breath of all things," before he could master Observation Haki.
"My thanks."
Closing his eyes once again, Don felt that strange sensation rise within him. When he opened them again, he gave a respectful nod.
"Since you've grasped Observation Haki, perhaps Armament won't be too difficult for you either."
Koushirou didn't waste time. He moved directly to explaining the second color of Haki.
"In my homeland, Armament Haki is called Ryuo—Flowing Sakura. It's a power born from within the body. Without sufficient physical strength, it is nearly impossible to wield.
This is a force that can flow, one you can channel and command. Once mastered, it provides tremendous offense and defense. More importantly, it allows you to strike at even the strongest Devil Fruit users."
As he spoke, Koushirou cast a meaningful glance at Don.
After all, the heat that sometimes radiated from Don's room was impossible to miss.
"So if Observation is the sensing of energy outside oneself, then Armament… is the channeling of some kind of energy within one's own body?"
Don quickly pieced it together.
Observation had been described as energy. By the same logic, Koushirou's words suggested that Armament was also energy—just of a different kind.
If he thought of it as inner qi, the concept became clearer to him.
There might be some differences, but the general meaning was likely the same.
"Mm… perhaps."
Koushirou fell silent for a moment, weighing the phrasing. Then he nodded.
"My strength is limited, so I can only explain according to my own understanding. Out there on the seas, there are many stronger than me. Perhaps my explanation of Observation and Armament isn't perfect."
"You're being modest, Master. Your strength is formidable."
Don shook his head slightly.
Even though he knew from the original story that Luffy would face countless powerful foes in the future—most of whom forced him into desperate battles—in truth, those were but a small fraction of the monsters roaming the seas.
And a true master swordsman like Koushirou was already among the highest tier of experts this world had to offer.
"Everyone has their own strengths and weaknesses. I know my limits, the ceiling of my talent. But you, Don…" Koushirou's gaze grew serious. "Your future, I cannot see through at all."
"That supposed to be a compliment?" Don chuckled.
"No. I'm merely stating a fact. This world is far from peaceful. And you—if you truly understand this world—should know what I mean."
The direction of the conversation made Don uneasy. He quickly raised a hand, diverting the subject.
"I heard that Armament is a power you draw out by imagining yourself clad in an invisible suit of armor?"
A clumsy shift in topic—but Koushirou let it slide.
He, too, realized he had said more than he should have.
After all, he had the distinct sense that Don would one day become a figure who could shake the entire world. And such people… no matter what they did, the consequences would ripple across the seas.
"You're correct."
Koushirou raised his arm before him.
Through Observation, Don perceived a layer covering his arm—a sheath of energy.
"This is the most basic application of Armament. When your reserves are sufficient, it manifests like this."
As he spoke, a faint purplish sheen encased his arm, resembling armor.
"And like this!"
He picked up a cup from the table.
The same aura flowed over it, cladding the cup in dark purple.
"Enveloping, flowing, Ryuo… these are all forms of Armament's use."
"I see." Don gave a slow nod.
"If you understand, then try drawing out your own Armament. But know this—it is no easy task. Many go their whole lives unable to awaken this power.
Though in your case, I doubt it will be too difficult."
Don lowered his gaze to his hands, tried channeling the energy—but nothing happened.
It was clear this would take time.
"There is one thing I must warn you of. Haki is not infinite. The more you expend, the longer it will take to recover. The amount varies from person to person—but in all cases, it depends on the strength of your body."
"I understand. I'll keep that in mind."
"Good. Then for today, that's enough. From tomorrow on, I'll personally spar with you. Battle is the fastest way to learn how to apply both swordsmanship and Haki."
Koushirou's eyes twinkled as he spoke, though his tone carried a sly undertone.
Not that Don had any intention of backing down.
He rose, gave his farewell, and left the room.
Once outside, he pulled out a scarf and tied it over his eyes, then activated his still-clumsy Observation Haki.
After all, the more he practiced, the better.
Even if overusing Haki could harm one's body, Don was exempt from such weaknesses.
In the dojo, Kuina was training alone with her sword, while in the woods behind, Zoro swung a bamboo sword weighted with stones, both hands straining with every strike.
Don, meanwhile, returned to his room and attempted to draw out his Armament again.
…
By dusk.
A modest merchant ship eased into Shimotsuki Village and docked at the pier.
The passengers disembarked, faces hidden beneath gray cloaks.
One, however, had a head that was far too conspicuous.
"Hurry it up. Once we've gathered the provisions, we leave immediately. Our identities are… sensitive."
The deep voice gave orders, and the others nodded silently.
The group moved swiftly, soon arriving at the front of the Isshin Dojo.
And there, waiting patiently as though he had expected them all along—stood Shimotsuki Koushirou.
"The food is ready."
His tone was calm and unhurried, as if this meeting had been arranged long ago.