Three days passed swiftly as Kenshi focused wholly on regaining his strength. He knew that he needed to heal fully first. Between long stretches of rest, he passed the time tending his sword, meditating, and poring over any texts he could find for useful information. 

He tried to communicate with the sword spirit but got no answers. He couldn't help but assume the spirit and system are identical twins since they only reply to him if they want to.

At last Shinobu told him that the meeting is going to be held. The next morning they set out for the Ubuyashiki household. Kenshi's anticipation mounted with each step they took. Finally he would have the chance to see the Hashiras and if he had chance, he would share some information from the manga, example being about the marks on Tanjiro's head.

After a steady travel they arrived at the sprawling Ubuyashiki estate. Shinobu led the way along the winding paths, past tranquil ponds and mossy stone gardens. Everywhere the sakura trees were in full blossom, petals drifting on the breeze.

Soon the main house came into view, an elegant structure with swooping gabled roofs. Shinobu glanced back at Kenshi as they mounted the steps.

"Remember, be open but not overzealous with the Hashira. Some may doubt your theories given that you're new, but stay composed."

Kenshi nodded, smoothing his features into a calm mask. Together they entered the quiet halls, removing their footwear at the doorway. Shinobu guided them towards the back of the house. As they neared what sounded like many voices, Kenshi realized all the Hashira must already be gathered. The thought quickened his pulse.

Shinobu paused outside the fusuma doors, turning to give Kenshi an appraising look. Then she slid the doors open. Kenshi followed her inside.

The spacious room beyond held over a dozen people seated formally on tatami mats. Candles flickered along the walls beneath hanging scrolls painted with plum blossoms. At the head of the room knelt a man Kenshi realized must be Master Ubuyashiki. His cloudy eyes stared unfocused ahead and bandages swathed his throat—yet an aura of deep wisdom emanated from him. 

Flanking the Master along each side sat men and a women bearing an air of lethal sharpness. Kenshi's gaze darted from flame-haired Kyojuro Rengoku, to the serene Muichiro Tokito, to the intimidating Gyomei Himejima and so on. So these were the legendary Hashira, the most powerful of all demon slayers...

As one, their piercing eyes turned to evaluate the newcomers. Kenshi withstood the weight of their combined focus, keeping his face neutral. Beside him Shinobu performed a graceful kneeling bow.

"Master, I have returned." 

Ubuyashiki's weathered face creased into a smile. "Welcome back, Shinobu. Please be seated." His voice was deep yet raspy.

Shinobu glided over to take her place among the Hashira. Kenshi followed, acutely aware of being the only non-Hashira present. He settled beside Shinobu and bowed respectfully towards Master Ubuyashiki.  

"Greetings Master Ubuyashiki. I am honored to meet with you."

The master inclined his head. "Well met, young Kenshi. I wished to speak with you directly regarding the unusual events in Sakurai Town. But first, let us clarify the situation for all present." He gestured towards Shinobu. "Please summarize what you reported to me earlier." 

Shinobu nodded gracefully. "Yes, Master." In concise terms she told them about finding Kenshi injured after defeating the demon, the gruesome experiments performed on townspeople, the enemy's apparent ability to revive after decapitation, and Kenshi's suspicions about the mysterious figure called Edward. The other Hashira listened intently, grim expressions on many faces.

When Shinobu finished, Master Ubuyashiki sighed deeply. "Most troubling. Experimenting on humans, creating demons...these actions threatens a great danger if left unchecked."

Murmurs of anger arose among the Hashira. Flame Hashira Kyojuro raised his eyebrows. "Unforgivable! We cannot let this wickedness spread!"  

The Stone Hashira, Gyomei Himejima's tears started running down his cheeks as he cried "How could anyone be so evil?!"

Calmly Master Ubuyashiki raised a hand for silence. "Peace. Anger clouds judgment. We must keep our minds clear." After a moment the Hashira settled, though tension hummed in the air.

Ubuyashiki turned his clouded gaze towards Kenshi. "Now then, young demon slayer. If the demon had not died  once you've beheaded it. how did you kill it?"

Taking a slow breath, Kenshi recounted what he already thought. "it died the third time I chopped his neck, I think he was not completely immortal."

The Hashira listened raptly, reactions ranging from shock to skepticism. 

Flame Hashira Kyojuro crossed his arms. "Hmph, sounds suspiciously like the wild tales my younger brother used to tell. Are we truly to believe this?" He said looking at other Hashiras.

"Now, now." Shinobu interjected gently. "What Kenshi said may seem unbelievable but with the amount of wild things we've seen before, it was not something I would dismiss as a lie. Unusual times call for open minds, do they not?" This earned solemn nods from a few of the Hashira.

Ubuyashiki raised his hand again. "I understand your doubts, but we cannot reject possibilities without thought. Let us hear the young man's full reasoning." He nodded for Kenshi to continue.

Choosing his next words carefully, Kenshi explained about a few scientific things about how these demons can be made in armies and how these glass Containers are used to hold them. "Forgive me, I do not fully comprehend these things myself. But the demon did not tell me all these things or anything about this 'Edward'. It was the mayor that uttered his name and this information."

Ubuyashiki smiled but contemplatively. "Hmm. Difficult to judge without seeing these materials firsthand. But a plausible notion." His clouded eyes reflected the candlelight. "We must keep watch for any others connected to this Edward, and determine his true motives."

The other Hashira nodded solemnly. Kenshi felt a small flare of satisfaction at having won over some of their doubts.

Finally Wind Hashira Sanemi Shinazugawa, marked face unreadable, spoke up. "Creepy experiments or not, the top priority is taking down any demons threatening humanity. My blade doesn't care where they came from or why they're here." He patted the sword at his hip. 

A nod of agreement came from Stone Hashira Gyomei. "Well said. We shall crush evil wherever it arises!" Flame Hashira Kyojuro and a few others also voiced approval of this simpler outlook.

Master Ubuyashiki held up his hand once more, expression thoughtful. "Your points are well taken. However..." He turned towards Kenshi again. "I would hear more of your perspective, young one. You seem to have some keen instincts and a very good intellect."

Kenshi chose his next words carefully. "I agree eliminating immediate threats is crucial. But to defeat an enemy, you must also understand them. This Edward has knowledge unlike anything we possess in this era. I believe learning more about him and his...unnatural skills, could reveal more vulnerabilities." 

He glanced around at the listening Hashira. "Or, perhaps offer insights to aid the Corps in new ways. Either would be valuable in combating him long-term." 

Ubuyashiki nodded slowly. "Wisely put. You have a methodical mind, young Kenshi." A hint of a smile touched his weathered face. "Very well. Our priorities shall be strengthening vigilance against demons, seeking any information connected to this Edward, and collecting intelligence on his abilities." 

Murmurs of assent came from the Hashira. Kenshi released a silent breath,.

Ubuyashiki smiled. "Good. Now then-" 

At that moment, the doors burst open with a bang. A young Demon Corps member stumbled into the room, panting heavily. "P-please forgive this intrusion, Master!" He gasped out. "But a dire report just arrived!"

The temperature in the room seemed to drop twenty degrees as the Hashira collectively tensed. Master Ubuyashiki merely nodded gravely for him to continue.

Still struggling to catch his breath, the messenger reported. "A horde of demons has been spotted gathering on Mount Natagumo! The few survivors who escaped from those demons speak of spider demons. All the demon slayers that are sent to deal with this threat are dead!" 

Instantly the Hashira were on their feet, hands clenching swords. Cries of anger erupted around the room.

Kenshi's mind raced as he realised, the Mount natagumo is the same mountain where tanjiro was captured. 'So the plot had already come to this point huh.' With the new enemy appearing, kenshi totally forgot about the original plot.

Master Ubuyashiki eyes became sharp as he said. "Swift action are indeed required. Shinobu and Giyu!" The named Hashira stepped forward resolutely. "You two depart at once for Mount Natagumo. Stop the destruction and slay the demons."