Facing Akaza's powerful physical techniques, Uchiha Nagi, naturally covetous, wouldn't give up easily, so he tried to integrate them into his sword skills.
After Akaza became a demon, he still adhered to the philosophy of a martial artist, creating the combat technique, Destructive Kill, which was based on human fighting spirit.
However, Akaza possessed the powerful regenerative abilities and immortality of a demon, so he never considered the damage the later, stronger forms would inflict on a human body.
Therefore, Uchiha Nagi could copy them but couldn't execute them because his speed and strength weren't sufficient, and his body lacked the necessary regenerative power and durability.
"Even if a Breathing Technique can strengthen the body, reaching the level required to unleash the final forms is extremely difficult~" Uchiha Nagi sat on the rooftop, stroking his chin in thought.
Similarly, Sun Breathing also requires an extremely powerful body to be used without repercussions. Thinking of this, Uchiha Nagi sighed. Was he destined to walk the path of physical enlightenment in the future?
But, it smells so good—
Considering the immense power of Sun Breathing and Akaza's Destructive Kill, it was impossible for Uchiha Nagi to give up. He was still hoping to learn more and more to take revenge on Konoha.
"Moshi moshi, Nagi-kun, sitting alone on the rooftop looking troubled, are you homesick?"
A girl's fragrance drifted on the wind, and a graceful figure slowly descended from the sky. This skill in concealment was unmatched by anyone except Shinobu Kocho.
Uchiha Nagi and his group returned to the Demon Slayer Corps to recover from their injuries, naturally staying at the Butterfly Mansion, as it was a place for healing.
"It's you, Miss Shinobu. I suppose I am homesick, but more than that, I'm thinking of revenge. That [home] isn't a real home; it only ever thinks of persecuting me..."
Uchiha Nagi sighed. Life for the Uchiha in Konoha was truly not easy. An Uchiha with a Three-Tomoe Sharingan had to be constantly wary of Root agents trying to dig out his eyes... "Just call me Shinobu. Miss Shinobu is too formal. My sister and others always called me that before." Shinobu Kocho smiled.
Uchiha Nagi blinked. He remembered that the first time they met, she called him Mr. Uchiha. When did she start calling him Nagi-kun?... His gaze involuntarily fell on her two crimson lips. Shinobu Kocho seemed to notice Uchiha Nagi's gaze, her face flushing slightly as she turned her head to look at the moon in the sky.
"Oh, right, Miss Shinobu, how is your understanding of Chakra coming along? Have you managed to extract it?" Uchiha Nagi asked.
Previously, Uchiha Nagi had taught the Demon Slayer Corps the basic knowledge of Chakra extraction, giving them a second cultivation system that could increase their survival rate through techniques like the Three-Body Technique or Medical Ninjutsu. Unfortunately, only the genius Muichiro understood and extracted it.
As for everyone else, not a single one had. Chakra is a combination of spiritual energy and physical energy, but most people here only understood physical energy, and even those who understood spiritual energy didn't know how to control and merge them.
"I'm so sorry, I understand both spiritual energy and physical energy, but I still haven't figured out how to merge them and extract them as Chakra after all this time..." Shinobu Kocho said with a regretful expression.
"I see, let me think..." Uchiha Nagi pondered, "Hold out your hand~"
"Eh?! Hand?" Shinobu Kocho looked puzzled but said nothing, extending her soft, boneless hand.
Despite years of sword training, her slender, jade-like hands showed no roughness, smooth and delicate.
Uchiha Nagi channeled his Chakra, which glowed green, and then slowly took Shinobu Kocho's slender hand. Shinobu Kocho's arm trembled slightly.
"Feel this. This is Chakra, and also the nature transformation of Chakra—"
After saying that, Uchiha Nagi transformed the green life-healing Chakra into his own fire-attribute Chakra.
Shinobu Kocho was a Pillar-level expert, so she immediately cast aside all distractions, closed her eyes, and focused entirely on sensing the components and changes of the Chakra.
If it were anyone else, or a man, Uchiha Nagi wouldn't bother; he'd tell them to read a book. But Shinobu Kocho... cough cough, beauties have privileges—
After a while, Uchiha Nagi stopped and explained to Shinobu Kocho the nature transformation of Chakra and how to merge spiritual and physical energy. This step sounds simple, but it is extremely difficult to do. However, once the first step is taken, the rest becomes much easier.
After half an hour of explanation, he started again, holding Shinobu Kocho's hand, letting her feel the nature transformation of Chakra, helping her remember and understand, and then asking about her comprehension and feelings.
Thus, the two of them stayed on the rooftop for several hours. By the end, Shinobu Kocho had a thorough understanding of Chakra; all that remained was time and luck.
"Thank you so much tonight, Nagi-kun." Shinobu Kocho smiled.
"You're welcome. You're a doctor. If you can extract Chakra and learn Medical Ninjutsu in the future, I'll also benefit, as everyone gets injured sometimes." Uchiha Nagi smiled slightly.
Uchiha Nagi's sudden smile was like an electric shock, leaving Shinobu Kocho momentarily stunned. The Uchiha clan's good looks were always present, especially Uchiha Nagi. He usually covered his face with shoulder-length hair and bangs, but the body he inhabited in this life possessed exceptionally high attractiveness.
He was in no way inferior to Uchiha Itachi and Sasuke, and compared to Itachi, who aged prematurely from overwork and had two nasolabial folds on his face, Uchiha Nagi had an even more refined aura. This was also why he wasn't mistaken for a bad person when he first transmigrated; good looks really could get you by... Shinobu Kocho quickly recovered, turning her head to look at the stars. "Oh, Nagi-kun, could you play your music? Although the melodies you play on the flute are a bit melancholic, I particularly love listening to them."
"Mm, sure. If you like it, I can teach you too." Uchiha Nagi nodded and took out his flute.
"Arigato, thank you so much. Unfortunately, I don't understand music, so I can't learn it~"
Uchiha Nagi smiled, said nothing more, and began to quietly play his flute. A mournful yet moving melody slowly drifted through the night.
It was as if it was reminiscing about something, or perhaps pleading, like a love longed for but forever out of reach.
When the song ended, Shinobu Kocho opened her beautiful eyes and asked,
"Such a moving piece. What is this song called?"
"It's called 'Lament'~"
Shinobu Kocho asked curiously, "Does this song, this name, have a story?"
Uchiha Nagi thought for a moment, then nodded. He supposed it did. "This is a folk tale about a love that spans a thousand years, about a girl named Kikyo who fell in love with a half-demon named Inuyasha..."
"Is that so? Kikyo is truly pitiful. The person she loved fell in love with her reincarnation. Even though it was her own reincarnation, it took away her beloved..."
Uchiha Nagi thought about it, unsure how to explain such a messy love story. However, Kikyo's situation reminded him of the Supreme Treasure from A Chinese Odyssey; the two were actually very similar.
"Buddha says there are three great sufferings in life: the pain of meeting those one hates, the pain of separation from loved ones, and the pain of not getting what one desires. Or perhaps, Kagome was specifically reincarnated to make up for Kikyo's lifelong regrets regarding love."