In the basement of the new mansion in Asakusa.
The large underground training ground created by Tamamo's space expansion sorcery was vast beyond comparison to the ordinary mansion above ground.
"Huff...!"
In the center of the training ground, Mitsuri was swinging a wooden sword, her cherry blossom-colored hair fluttering.
She was trying to master Flame Breathing by observing Shinjuro's breathing and sword techniques from Akira's memories, but it didn't suit her unique physique, and she was struggling.
However, the confidence gained from being with Akira, and her intense love-driven desire to protect her family, transformed her swordsmanship.
"Faster... more flexibly! With strength that bends like a whip but never breaks!"
Mitsuri's eyes changed. She merged the heaviness of Flame Breathing with the flexibility of Flower Breathing, drawing a bizarre yet beautiful trajectory that utilized her innate muscle strength and joint range of motion to the limit.
"Love Breathing, First Form!"
Her wooden sword danced through the air as if slashing it.
"First Love's Tremor!"
Whoosh!
It was a single swing, but the afterimage of the wooden sword curved like a whip, simultaneously striking five dummies in front. Not a simple slash, but a destructive shockwave shattered the dummies into pieces.
"I did it! I did it!"
Mitsuri jumped up and down as she looked at the shattered dummy remains.
"Akira-san! I finally created my own technique! This is my breathing!"
Akira, who had been watching, clapped and approached.
"That's amazing, Mitsuri. It's a technique that no one else can imitate without your muscle strength and flexibility. It's truly wonderful."
"Hehe... I named it Love Breathing! When I swing it while thinking of Akira-san, I feel power surging, you know?"
Mitsuri, drenched in sweat, hugged Akira tightly. Akira patted her back and turned his gaze aside.
There, the small-framed girl, Kanao, was silently swinging a wooden sword.
She was building the basics of Flower Breathing under the guidance of Kanae and Tsubaki. Although her lung capacity was still insufficient, making it hard to maintain breathing, Kanao's eyes were unwavering.
'Everyone... is getting stronger.'
Akira smiled contentedly.
And that evening.
Before the heat of training had cooled, another kind of war, much more dangerous and heated, was unfolding in the living room.
The topic was who would claim Akira's futon tonight.
The first to open fire was, as expected, Shuten.
"Hmph~ Since the little ones (Kocho sisters) monopolized you yesterday and the day before, isn't it my turn to comfort you today, Master? You must be missing the rich taste of an adult."
Shuten tilted her sake cup and provocatively loosened her yukata, revealing her cleavage.
Shuten, using her demonic nature as an Oni-type demon, had changed her physique for the first time in a while. Her body was voluptuous, akin to Ibuki Doji.
Then, Tamamo covered her mouth with a fan and sneered.
"My, Shuten-san. A bed smelling of alcohol is harmful to Master's health. Today, I, who have been working hard recently, should relieve fatigue and receive magical energy from Master."
"Master needs to rest properly. If he does it with all of you, Master will become a dried squid. So today, I'll let him use my arm as a pillow."
As Benienma rolled up her small sleeves and stepped forward, suddenly, Tamamo Cat, who had been crawling on the floor, stood up and barked.
"Woof! Today's Master is my prey! Therefore, today I will bake shokupan on Master's stomach! Cat Punch!"
At that moment, Ushiwakamaru's eyes sparkled as she grabbed her scabbard and jumped out.
"If it's night guard duty, it's the role of this warrior, Ushiwaka! I will take responsibility for the safety of the bedroom! Of course, the safest place is in Master's embrace, so I will enter there!"
"Wait, Ushiwaka-san! That's unfair, going ahead alone!? I'm a warrior too!? Tonight, the guard and bed partner for Master will be taken by the genius swordsman, Okita-san! Come on, Master! Sleep with me!"
Okita fluttered her haori and fiercely cut in. She clung to Akira's arm, her eyes sparkling.
In the corner, Hokusai (Oei) was holding a brush and laughing.
"Totosama said that the completion of art is the exploration of the body. Master, be my model tonight. Of course, no clothes are needed, right? I'll explore every inch of that sturdy body with my brush~"
She licked her lips as she scanned Akira up and down, wriggling her fingers.
Following that, Kocho Kanae smiled sweetly and stepped up.
"My, everyone is so lively. But Akira-san recently promised to take responsibility for me and Shinobu, didn't he? In a way, we're like newlyweds, so using separate rooms isn't right."
"That's right. And for my poison research, I need more information on Akira-san's body."
Shinobu added with a slightly red face from the side.
Even Tsubaki, who was in the corner, quietly raised her hand.
"...As Master's sword, I believe night guard duty is also my task."
"Everyone, move aside!! Master is mine!"
Kiyohime finally exploded, about to emit blue flames.
"Kyaa! Everyone is too wild!"
Mitsuri blushed and didn't know what to do, but she was stealthily eyeing the spot next to Akira.
At that moment, Ubume, who had been quietly observing, raised her hand.
"...I want to do it too."
Her face was red, but her voice was plain and firm. The short, thick statement made the room fall silent for a moment.
Watching this chaotic scene, Nobbu chewed on senbei and laughed.
"Hahaha! It's tough being popular! Isn't this the Warring States period? Akira, I wonder if your waist will survive! You might not even have bones left!"
Of course, she was also fully intending to participate. Her attire was very light.
Akira stepped back, sweating cold sweat. This wasn't a happy scream, but a matter of survival.
"W-wait! Today, I need time alone to sort out my thoughts!"
At Akira's shout, the eyes of over ten women simultaneously flashed like beasts.
"You can sort out your thoughts on the bed, can't you?"
Eventually, that night, Akira had to give up on sleeping alone.
On the wide bed, with Akira at the center, on the left were the Kocho sisters, Tsubaki, and Mitsuri; on the right were Shuten, Tamamo, Kiyohime, and Hokusai; at the foot were Tamamo Cat, Ushiwakamaru, and Benienma; and squeezing into the gaps were Okita, Nobbu, and Ubume.
He truly became a human (demon) sandwich and had to endure all night.
And at dawn.
Akira, who had barely escaped from the tomb of female tribulation, came out to the terrace with hollow eyes.
Due to Tamamo's bedroom techniques, Benienma's stamina-recovery onigiri, the aphrodisiac and Viagra-like things made by Shinobu, and Tamamo's sorcery that made time flow differently inside and out, Akira had been squeezed for nearly 20 hours.
The cold dawn air cooled his heated and exhausted body.
Akira looked down at his own hands. Strong. Clearly stronger. He had power that could easily crush ordinary demons or Lower Moons.
'But... this is it. To truly endure these nights, even being an Upper Moon One might not be enough. I'm afraid it might increase further. I'm even afraid to summon more Servants.'
Akira coldly analyzed his current position.
'Currently, I can overwhelm Lower Moon Six, Daki. But if I fight her brother Gyutaro? I expect to be at least equal or win. But it wouldn't be overwhelming, and I'd win with considerable damage. If I fight Lower Moon Five Gyokko or Four Hantengu, victory is hard to guarantee. No, I might turn into a fish from Gyokko's Divine Hands. Of course, Tamamo's sorcery barrier would offset it, but I'm likely weaker than Gyokko.'
A growth plateau had come. Simply eating humans or demons had its limits.
'I need the blood and flesh of stronger demons.'
The demons he had eaten so far were at best Lower Moon level. In the original, Muzan slaughtered the Lower Moons for being too weak. Akira reached the same conclusion.
'Lower Moons... are meaningless now.'
Then, only one thing remained. It was time to eat all the remaining Lower Moons and leave only the Upper Moons to fight when ready.
A name of a place and a demon came to Akira's mind.
Mount Natagumo. And the Lower Moon Five who ruled there, Rui.
'Rui is special.'
Although numerically Lower Moon Five, he is a demon favored by Muzan.
Muzan shared quite a lot of his blood with Rui and even allowed him to play family. That means Rui's body flows with a high concentration of Muzan's blood.
His power is practically close to Lower Moon One, and with the shared Blood Demon Art, Molting, if he actively hunted humans, he could be expected to grow to at least Daki's level.
If he had strived for strength rather than playing family, he would have properly secured the position of Lower Moon One, on par with Daki.
'If I absorb Rui... I might be able to surpass Gyutaro for sure.'
Moreover, in the original, Rui is the catalyst that causes Muzan to disband the Lower Moons. With Rui's death, Muzan feels the uselessness of the Lower Moons and carries out a purge.
'I'll make the first move.'
There's no respect for the original. Since things have already diverged greatly from the original, there's no need to consider the original story.
Overwhelm Mount Natagumo with absolute power and consume Rui. Who knows what might happen?
Rather, from this incident, Muzan might sense a crisis and mass-produce Lower Moon-level demons.
"...I must go."
Akira tightly gripped the terrace railing.
Akira's eyes glowed red. The comfort of Asakusa was only temporary. To gain greater power, he began preparing to move his steps to the forest tangled with spider webs.
"Spider Father's Molting is useful. His power is roughly at the next level after Lower Moon, so he could be our gatekeeper. Although he looks ugly. As for the others, just kill them all. I don't need to increase the number of women anyway."
He didn't even consider Spider Brother. Spider Sister? Not his taste, and the Blood Demon Art isn't great. Spider Mother? Her appearance is to his taste, and the Blood Demon Art isn't bad. But there's no need to recruit her.
Since even Tanjiro-level could be countered, it's enough to simply bring Spider Father, who has good strength and growth potential.
A predator's smile hung on his lips, and for the first time in a while, his next prey was decided.