A year had passed since the subjugation at Mount Natagumo.
With the seasons turning, it was the autumn of 1910, and the streets of Asakusa had become even livelier, riding the winds of civilization and enlightenment.
The Asakusa main branch of the Akatsuki Trading Company had become a landmark of the street.
In the logistics warehouse, bustling movements continued even today.
"Hey, Kumoeimon! Move 10 sacks of rice to warehouse number 3!"
"Uoooo... R-roger."
The large-framed man, Kumoeimon (formerly Spider Father), lifted 10 sacks of rice at once with his thick arms. Among the porters, he was known as the strong, mute laborer.
His non-human face was concealed by magic, and thanks to his diligence and excellent strength, he had become a reliable worker who took on the company's tough jobs.
Inside the store, an elegant beauty was attending to customers.
"Oh, customer. That silk is a new item that just arrived from Kyoto. It would suit someone with beautiful skin like yours perfectly."
It was Kumonojo (formerly Spider Mother). She had now perfectly adapted to human society.
To her original alluring charm, the gentle smile she learned from Mukago was added, to the point where male regular customers lined up just to see her.
"Hey! Kumohime! You haven't wiped that table over there! I told you to move briskly!"
"Ah, I know! I'm doing it now! Mukago-san is always picking on me!"
Kumohime (formerly Spider Sister) grumbled but diligently wiped the table with a cloth. And behind her, with arms crossed, was Mukago, keeping watch.
"Hmph, without me, this company wouldn't run. There's a reason the master trusted and assigned me."
Mukago had now become as strong as Lower Moon One, on par with Enmu and Bibil. However, she still felt greater satisfaction in this role as a neighborhood boss rather than in combat.
To begin with, those weaker than her were even fewer, so she had no reason or necessity to act as a combatant, which is why she was helping with company work like this.
Under her command, the former spider family had become indispensable cogs in the Akatsuki Trading Company.
They had received names, albeit hastily, from Akira during the Mount Natagumo incident. Now having forgotten their past names, they worked as members of the company with new names.
Unlike before, it was a life of working like humans, but it was much better than the life on the mountain, living under Rui's fear.
First, they could live a cultured life. Wearing good clothes and living in a good house, eating the food provided by the house, it was a much more affluent life.
Moreover, living only on the mountain would have made the repetitive life more tiring, but here, meeting people and being active made them feel truly alive.
Especially, thanks to Tamamo's magic, they could even be active under the sun.
As the avatar of the sun god, it wasn't difficult for her to cast magic that blocked the sun's power, allowing them to be under the sun for at least 2 hours, up to 4 hours. Not that they were under the sun all the time, and since they spent more time indoors, it was fine.
For the spider family, it was incomparably better than their previous life, so everyone was living satisfactorily without complaint.
Meanwhile, in the underground training ground of the mansion.
A year was a long time for swordsmen to grow.
Clang!
With a sharp cracking sound, Mitsuri's soft blade bent like a snake and thrust in. But the girl who read its trajectory dodged the sword by a hair's breadth and counterattacked.
"Kanao-chan, you've really improved a lot! My attacks aren't hitting well anymore?"
Mitsuri wiped her sweat and smiled brightly. Across from her was Tsuyuri Kanao, regulating her breathing.
The girl who once lived as a slave, giving up everything and having no self-determination, was no more. Her eyes were deep and clear, and within them resided a firm sense of self.
"Mitsuri-nee's sword is fast. But... I can see the trajectory. So I was able to read it."
Kanao had grown into a hybrid swordsman who absorbed both sisters' techniques: Flower Breathing and Insect Breathing.
On top of that, she learned Water Breathing, the origin of those breathing styles, from Tsubaki, becoming a swordsman who uses three breathing styles.
Her best affinity was Flower Breathing. But since its origin is Water Breathing, and Insect Breathing is a derivative of Flower Breathing, she had no great difficulty using them.
Kanao's eyesight was very exceptional, and her talent did not fall short compared to the Hashira of the golden generation.
Kanae and Shinobu, who were watching, smiled contentedly.
"Our youngest has grown up now. Shinobu, won't she surpass us at this rate?"
"Oh, sister. There's a saying that the student surpasses the teacher. But... she's not there for me yet, right?"
Shinobu laughed playfully, but from the sword at her waist, a chilly aura flowed.
Over the past year, she had continued to receive teachings from Ushiwakamaru, fully embodying the Tengu footwork, and now could tread on air as if walking on flat ground.
Kanae also honed Okita's footwork further, reaching a level where even the moment of drawing her sword was invisible.
The Kocho sisters, taught by genius swordsmen. With their outstanding talents overlapping, they grew rapidly in a short time.
They were now at a level that could not be bound by the rank of Hashira in the Demon Slayer Corps, and were recognized by Akira as Servant level.
Of course, that's limited to swordsmanship using breathing styles. In terms of overall combat power, they couldn't withstand Kiyohime's wide-range flames, after all.
Even if their swordsmanship was excellent, they didn't have bodies as powerful as Servants like Okita and Ushiwakamaru, who are also swordsmen, nor special abilities like Kiyohime or Tamamo, so it was only natural.
Still, at the point where they could fight Servants in swordsmanship alone, their abilities were outrageous.
"I can't even be a match now. I just can't keep up with the four of you's talent, can I?"
And Tsubaki, the swordsmanship instructor and company guard.
She had continued training over time, honing Flower Breathing and the Water Breathing she learned before. Her skill had grown to a level where she could engage in battle with Lower Moon Six and secure victory.
But even so, she was the weakest here. At best, she was on par with the spider family.
The limit of talent. Tsubaki looked down at her hand holding the sword and felt anxiety, wondering if she would be of no help at all from now on.
Meanwhile, behind the prosperity of the company and the growth of the group, a heavy silence hung in the master Akira's office.
"...Sigh."
Akira looked down at the reports piled on his desk and sighed.
Over the past year, he had expanded his influence with Asakusa as a base, chasing Tamayo's traces. But he couldn't even catch her tail.
Whether she hadn't come to Asakusa yet, or she noticed their existence and didn't come.
A bigger problem was the demons' movements. Despite Rui's disappearance, reports of Lower Moon-level demons still came from the regions.
'That bastard Muzan, knowing that I'm devouring the Lower Moons, he's still replenishing them. Is he planning to buy time and keep me in check? He probably doesn't know about me, and thinks it's a new organization like the Demon Slayer Corps. To maintain the Lower Moons even after Rui's death.'
Rui's death should have been the trigger for disbanding the Lower Moons. But Muzan, for some reason, was still creating them.
Knock knock.
"Father, may I come in?"
With a quiet voice, the door opened, and Kanao entered. In her hand was warm tea.
"Kanao? Is training over?"
"Yes. ...Father, your expression is dark. Is it because you couldn't find that Tamayo person again?"
Kanao placed the teacup and looked straight into Akira's eyes. It was a direct way of speaking unimaginable in the past. Now, she could read his heart just from his subtle facial changes.
"Lying is useless. I can see it."
Soon after, Mitsuri also barged in carrying a bunch of special cherry blossom rice cakes she learned from Benienma.
"Akira-san! Cheer up! I just made these, and they're super delicious! They say sugar intake makes you feel better!"
With Mitsuri's bright energy, the heavy air in the office dispersed a bit.
"Master~ It's mealtime!"
Finally, Tamamo Cat came in pushing a cart.
On the plate was an omelette rice covered with yellow rolled egg. But inside, instead of rice, there was a steak cooked blue-rare, made from premium human thigh meat.
The egg was soft-boiled, and thanks to becoming somewhat stronger and gradually improving his body with Tamamo's magic, he could now eat even undercooked eggs.
"You've been totally~ lacking appetite lately! We maximized the meat juices, meow! Eat up and get stronger, Master!"
Akira smiled bitterly at the women worrying about him.
"Everyone… thank you. I guess I was too impatient."
It was the moment Akira was about to lift his spoon.
Bang!
The office door opened roughly, and Ushiwakamaru, having lost her usual composure, rushed in.
"M-Master! We found it! Finally!"
"What? Tamayo?"
Akira's eyes flashed as he rose from his seat.
"No! Something even more important…! It came through the company's information network. In the western part of Tokyo, in the Okutama district, Mount Kumotori. A family that makes and sells charcoal lives there…."
Ushiwakamaru caught her breath and spat out the words Akira had been waiting for so long.
"They're called the Kamado family!"
Instantly, Akira's pupils dilated. His heart began to pound fiercely.
Tamayo? No, she's not the issue now.
The mountain where the protagonist of the original work, Kamado Tanjiro's family, lives. And there, it exists.
The Blue Spider Lily.
The herb that turned Muzan into a demon, and at the same time, the key to becoming a perfect being that overcomes the sun.
"Ha... hahaha! Finally! Finally found it!"
Akira clenched his fist tightly. It felt like a year of waiting and stagnation was rewarded in an instant. Upper Moon hunting? Muzan? Those were now secondary issues. If he could just get the Blue Spider Lily, he wouldn't fear even a one-on-one with Muzan.
"Ushiwaka! Prepare to depart immediately! We're taking all our Servants!"
At Akira's shout, the entire mansion went into emergency mode. His gaze burned more greedily and intensely than at any time in the past year.
"Sorry, everyone. It's urgent, so just us will go and come back. We'll be back soon, so don't worry."
Akira put on his outer coat and gave a bitter smile.
"If it's the Blue Spider Lily, that's it, right? What you told us before."
Then Shinobu and Kanae entered the room.
"Please take us too. We're confident in pharmacology."
"Yes, we won't get in the way."
As Shinobu and Kanae earnestly pleaded, Akira nodded. The research could be done after returning, but seeing the habitat might provide clues to find other habitats.
And so, to obtain the Blue Spider Lily, they headed for Mount Kumotori.