Just as she said, Shinobu Kocho did nothing beyond drawing Takeo's blood.

Later, Takeo realized that the reason Shinobu Kocho had used such gentle words to "threaten" them was because she had genuinely been angry about the injuries they had sustained during their fight.

But once her anger subsided, she returned to her usual self.

The main reason was that Muichiro recovered very quickly. Within just a few days, his injuries had completely healed.

"Although the human body isn't as resilient as a demon's, with the aid of the Breathing Techniques, even a human can possess recovery abilities far beyond the average person's… though still not comparable to demons—or to you," Shinobu Kocho remarked.

She was mixing something using Takeo's blood. At last, she poured the solution into a test tube, sealed it, and placed it inside a box beside her.

"The conditions here are still too limited. We'll need to return to the Butterfly Mansion to properly analyze the results."

Takeo didn't know what she intended to do with his blood, and he didn't ask.

As Hashiras, there existed a fundamental level of trust between them. They didn't ask questions that didn't need answering. This unspoken understanding held true between Takeo and Shinobu Kocho.

However, though Takeo didn't ask, Shinobu Kocho spoke up on her own.

After she had packed her things, she turned to him and asked:

"Aren't you curious what I'm doing with your blood?"

"Not really."

"Ah, aren't you worried I might do something bad to you? After all, your recovery ability is something anyone would envy," Shinobu Kocho asked with a smile.

Takeo sat cross-legged on the corridor, basking in the sunlight with his two Nichirin swords resting on his knees. He appeared to be meditating. At her words, he slowly opened his eyes and looked at Shinobu Kocho.

"I trust you," he said calmly.

"That's really…" Kocho Shinobu paused for a moment, clearly taken aback. Then she shook her head helplessly and finally said, "Well, it is your blood, after all. There are some things I should explain to you."

"I want to use your blood to study the secret behind your extraordinary recovery ability. If I can replicate even a fraction of it… maybe, just maybe, fewer people in the Demon Slayer Corps would have died."

Shinobu Kocho spoke frankly.

Ever since discovering Takeo's powerful regenerative ability, she had harbored this idea.

Normally, Shinobu didn't concern herself with others' unique physiques, but when it came to recovery ability, she couldn't ignore it.

Just imagine—if the other Hashira could possess a similar level of regeneration, even just one-tenth of Takeo's, their combat endurance would rise dramatically.

Perhaps in a future life-or-death battle—one that should end in tragedy—they might be able to survive, all thanks to improved recovery.

This was something that affected every member of the Demon Slayer Corps, and Shinobu couldn't help but care about it.

After hearing Shinobu Kocho's words, Takeo nodded in understanding. Not only did he understand—he agreed with her completely.

Takeo nodded and said, "If you need blood in the future, you can come to me directly."

Shinobu Kocho wanted more people to survive—and in that regard, Takeo felt the same.

He even wondered, if Iori and Asato had possessed the same recovery ability as him, even if just a weaker version, would they have been able to survive?

But no matter how much he thought about it, the dead would not come back to life.

All Takeo could do now was prevent more people from dying, to stop more tragedies from happening.

And Shinobu Kocho's goal aligned perfectly with his.

Since Shinobu Kocho's Nichirin sword only needed repairs, she didn't stay long in the Swordsmith Village before leaving.

That same day, Muichiro—who had arrived much earlier to have his sword reforged—also left the village to resume his duties as a Hashira.

In the end, Takeo was the only Hashira left in the Swordsmith Village.

After all, he wielded two swords, and forging and tempering both of them would naturally take more time, so he had to stay longer.

However, Takeo wasn't bored during this time.

Because—Tanjiro received a letter.

As expected, Giyu Tomioka had told Tanjiro about Takeo. And after Tanjiro smelled the scarf Takeo had given him, he immediately confirmed his identity.

A few days later, his letter arrived in Takeo's hands.

...

Takeo, long time no see… how are you?

I've heard from Mr. Giyu that you're still alive… That's great. Besides Nezuko, I still have family in this world. It's really great…

But at the same time, I'm also very sorry. I'm sorry, Takeo. I'm really sorry. I didn't check carefully that day and didn't find that you were still alive. I didn't take you away with me. I'm really, really sorry!

When we meet, hit me! Even if you break my bones with your fists, I will never resist!

Also, I heard that you also joined the Demon Slayer Corps and almost became a Hashira? That's amazing. I have to keep working hard as your brother too!

Oh, oh, I forgot to mention that I am currently training under Mr. Urokodaki. Training with Mr. Urokodaki is really hard. Every day I have to dodge traps and swing swords. Recently I have to learn Breathing Techniques, but I cannot master the breathing rules and I am always beaten by Mr. Urokodaki.

He said to breathe with your belly… it's really hard to understand.

But I will try my best! My brother has become so strong, and as his elder brother, I must at least not hold him back!

And… I heard from Mr. Urokodaki that you seem to have lost your memories of the past? I don't know how much memory you still have of your family, but it doesn't matter even if you've forgotten everything! I will tell you bit by bit!

I'm sorry, I said a little too much in this first letter. Mr. Urokodaki is urging me to go to training again. I'll talk about the rest next time!

——Kamado Tanjiro

...

The content of the first letter wasn't very long. It mainly expressed Tanjiro's joy at discovering that Takeo was still alive, as well as his deep regret for not realizing it that day.

It was clear that he had been genuinely excited, happy, and remorseful.

The letter was covered in wrinkles and water stains, suggesting that Tanjiro had likely been crying as he wrote it.

The first letter was sent on the day of Takeo's duel with Muichiro, but because it had to be delivered through the Kakushi, it didn't reach Takeo until the next day.

Then, on the day Shinobu Kocho left, the second letter also arrived in Takeo's hands.

...

Takeo! Congratulations on becoming a Hashira! That's amazing! So amazing! I'm really happy for you! I'll have to work even harder now too!

But Takeo, while being a Hashira is great, please take care of yourself and don't push too hard! Also, please try not to get hurt, or else your brother and sister will be very sad!

So please, look after yourself!

By the way, I don't think I mentioned Nezuko's situation? Your sister Nezuko is doing well right now. For some reason, I can't tell you the details, but don't worry—she's safe, and your big brother will protect her and you!

Even though it seems like you don't need my protection right now… I'll still keep working hard! Yeah! Keep working hard!!

…I've recently learned some clues about the Breathing Technique from Mr. Urokodaki. The sensation of the body being strengthened is called 'Total Concentration Breathing.' I heard you mastered it in less than a day. That's incredible. I'm a little ashamed.

Oh, I almost forgot—I still want to talk to you about our family. Where should I start?

Let's start with Rokuta. Rokuta was the youngest in the family, our little brother. If he were still alive… he would be four years old this year…

...

The handwriting here was blurred in places, likely from tears, but it didn't affect readability.

In the latter part of the letter, Tanjiro focused on describing Rokuta's personality—what he liked and disliked, who he enjoyed spending time with the most, and what games he liked to play in daily life.

_________

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