"A firefly's glow dares to contend with the bright moon!"
Boom!
A colossal figure made of flame Chakra appeared, enveloping Uchiha Nagi's body. It was Susanoo.
At first, it was just a skeleton. Rui's Blood Demon Art struck the Susanoo, only advancing a few inches before being completely halted by the bones.
"Ho-how is this possible?!" Rui was shocked. What was this thing? He had never heard of a Pillar possessing such a skill, one that resembled a Blood Demon Art.
Immediately, the skeletal Susanoo swung a long sword of flames—the Sword of Totsuka—and with a single strike, it severed all of Rui's Blood Demon Art, Thread Rotation.
Then, the Susanoo began to evolve ceaselessly, gaining flesh, an outer garment, and finally transforming into a giant as large as a small mountain.
"Wh-what is this thing?!" Rui muttered to himself.
"What is that—?" Giyu Tomioka looked curiously at the giant that suddenly appeared in the distant forest. Such a towering figure was visible to anyone who wasn't blind.
Arriving at the battlefield, he just saw a spider woman in a white kimono [Rui's older sister] about to attack Tanjiro and Inosuke, who were severely injured and unable to fight.
Tanjiro was immobilized due to the after-effects of Sun Breathing, and Xiao Zhuzhu Inosuke, suffering from severe blood loss and nearly having his head crushed by the spider giant, was also unable to fight.
Then, Nezuko, who was hiding in a wooden box nearby, jumped out to fight the opponent to protect her brother.
Water Pillar Tomioka Giyu, seeing this, instantly killed her with a single move. Afterwards, the suicidal Xiao Zhuzhu Inosuke, upon witnessing Giyu's strength, challenged him.
He was promptly tied up and hung from a tree by Giyu Tomioka. Just as he was about to say a few words to Tanjiro, he saw a giant made of energy appear in the distance—it was Susanoo.
Of course, they didn't know what it was, even suspecting it to be a skill of the Twelve Kizuki, because Pillars only knew Breathing Techniques.
"That's Nagi-aniki's (Nagi, older brother) area." Tanjiro struggled to get up, "We... we have to go support Nagi-aniki (Nagi, older brother)."
"No, you just wait for the reinforcements to heal you. Leave it to us." As soon as he finished speaking, Water Pillar Tomioka Giyu had already disappeared, rushing towards the giant at the fastest speed using Water Breathing.
On the other side, a woman with a butterfly hairpin also saw it. She was currently treating Zenitsu.
This unlucky fellow, Zenitsu, encountered another spider person [Rui's older brother] and was secretly bitten by a small spider, almost dying from poison.
Fortunately, after he fainted, his subconscious personality emerged and instantly killed the spider person. Then, as he cried and grieved over his impending death, his little sparrow fluttered its wings and found Shinobu Kocho.
"Moshi Moshi~, you should be fine now. I need to go help over there. That giant doesn't look easy to defeat. I wonder which of the Twelve Kizuki it is." Shinobu Kocho smiled and patted Zenitsu's head, then leaped down.
Like a butterfly, she used her Breathing Technique and swiftly flew towards the yellow giant.
"Compared to Madara, it's still several times smaller~" Uchiha Nagi looked at his Susanoo. Although it was tens of meters, nearly a hundred meters tall.
But compared to Madara's Susanoo, which was like a mountain, it was the difference between a child and an adult.
The reason for activating Susanoo wasn't to show off, but because any Ninjutsu caused minimal damage to Rui. His physical recovery speed was extremely fast, and his skin was incredibly hard, comparable to the Third Raikage's.
And every one of the Twelve Kizuki was like this, extremely troublesome. Amaterasu would be useful, but given his recovery ability, he would likely just cut off the burned body part with his threads immediately, just like the Raikage.
What was more troublesome was Rui's omnipresent, hard, and sharp long-range thread attacks. If Uchiha Nagi were cut, he would be dismembered.
In that case, it would be better not to use it and save some energy, so directly unleashing the Susanoo's ultimate move was the best option—absolute defense. Clearly, Uchiha Nagi made the right choice.
Rui's Blood Demon Art simply couldn't break through Susanoo; it could only cut the outermost layer. As he expanded Susanoo to cover his entire body, the opponent's Blood Demon Art became completely useless.
"This, how is this possible!! What kind of Jutsu is this?" Rui, refusing to believe, once again unleashed his ultimate move.
"Blood Demon Art—Thread Rotation."
This time, Rui's Blood Demon Art was even more massive, directly covering the sky and earth. The few remaining large trees nearby were pulverized into wood chips by the invisible threads.
[This is bad—] The Water Pillar, Giyu Tomioka, who was rushing from afar, saw Rui using his Blood Demon Art. And the Insect Pillar, Shinobu Kocho, who was right behind him, also sighed inwardly, clearly realizing that neither of them would make it in time.
Uchiha Nagi, however, laughed wildly, "Hmph, do you think you can dance with me?"
Uchiha Nagi controlled Susanoo, raised Susanoo's exclusive sacred sword, Sword of Totsuka, and brought it down forcefully. Although Sword of Totsuka was a ceremonial sword with little power in its physical state, its power was immense in its spiritual state.
Susanoo wielded it, directly cleaving Rui's Blood Demon Art, scattering it everywhere. Then, in the instant Rui frantically tried to escape, Susanoo cut him in half.
"Those pierced by the Sword of Totsuka will have their souls sealed in a world of drunken dreams. Rest in peace~" Uchiha Nagi said indifferently.
Subsequently, Rui's body began to recover, but his eyes were blank and tearful, because his soul had already been sealed. Once the morning sun rose and his body turned to ash, he would be dead.
"Moshi Moshi, this young man doesn't seem to be from our Demon Slayer Corps, does he? He seems to have killed a Lower Rank Demon." Shinobu Kocho, floating lightly as if flying, slowly descended, though she did not relax her guard.
For instance, if Susanoo's mountain-like body stepped on them, they would be instantly turned into meat paste. Humans like them didn't have the immortality of demons.
"As long as he's not a demon, it's fine..." Water Pillar Giyu Tomioka said expressionlessly.
Uchiha Nagi, of course, also saw them. Accompanying them were Tanjiro and Xiao Zhuzhu Inosuke, who were severely injured but still insisted on coming to support.
"Sugoi... Nagi-aniki (Nagi, older brother) is truly too strong." Tanjiro, supported by his sister, and Inosuke hadn't even gotten close when they saw this giant.
"Damn... damn it, why are so many people suddenly stronger than me? It's infuriating, #." Inosuke was indignant. He had originally planned to surpass Uchiha Nagi, and now there were two more.
Seeing Uchiha Nagi on Susanoo's forehead, looking like a deity, Inosuke, while angry, also felt a touch of envy, fantasizing about piloting such a giant. Wouldn't he just stomp on demons one by one?
Imagining himself crushing those things like cockroaches, he couldn't help but burst into laughter. Giyu Tomioka looked at Inosuke and couldn't help but roll his dead-fish eyes, "Is this guy sick...?"
Seeing that several people had arrived and the strongest Rui had been defeated, Uchiha Nagi naturally stopped piloting the 'Gundam.' Susanoo began to slowly dissipate, finally descending to the ground.
"Hello everyone, I am Uchiha Nagi."