Inside the laboratory, Nanatsuki and Aizen were reviewing and cataloging the gains from their recent operation.
"Tsunayashiro Tokinada was really resurrected in Hell, huh…?"
Nanatsuki was speaking with Shihoin Yoruichi via Denreishinki, but since Hikifune Kirio's lab could monitor communication signals, they didn't delve deep into sensitive topics.
After recounting the night's events, Yoruichi hung up.
"Sosuke, our plan worked. They've completely accepted that it was Tsunayashiro Tokinada's doing," Nanatsuki said with a chuckle.
"The escaping servants, the Shinigami who 'followed Tokinada' into the manor, the nearby residents — they're all our witnesses."
There were plenty of eyewitnesses who "saw" Tokinada and the Gate of Hell.
He and Aizen had deliberately let many servants flee. These weren't clan members — and more importantly, they served as eyewitnesses to Tokinada's appearance.
With so many sources corroborating the same story, there was no room left for doubt.
"Sensei's plan was flawless," Aizen agreed.
"Everyone saw Tokinada wielding the Tsunayashiro clan's ancestral Zanpakutō, Enrakyōden. That alone guarantees no one in the 13 Divisions will suspect he was a fake."
"We've gained quite a lot tonight…"
Nanatsuki began unpacking the items he had brought back from the tower.
The bulk of it consisted of books.
The Tsunayashiro clan's library was in the same building as the Soul King fragments and Enrakyōden, so he had taken their entire archive.
Next were ancient relics and Tenshihō Banshōban artifacts.
The relics weren't immediately useful to him, but could be sold later for research funds — though not right away, as the heat was still on the clan.
Once things cooled down, Yoruichi could help with that.
Aizen focused on organizing the books, while Nanatsuki sifted through the Tenshihō Banshōban items.
"Let's sort these first and pick out the useful ones."
The items stored in the treasure tower were mostly collectibles — not all were practical.
Tenshihō Banshōban were tools or weapons with special functions.
Their appearances didn't always reflect their abilities, but thankfully, most had accompanying manuals or descriptions.
"So flashy…"
Nanatsuki understood why they were grouped with the relics.
Many were ornamental, like the Everblooming Hollow Flower — a rare creation crafted from a plant-type Hollow. Its center was a Hollow mask, and its leaves were made of bone.
"Soul Chain… reconnects the soul to the Reiatsu Particles body? That could mean resurrection!"
He had discovered a particularly interesting Tenshihō Banshōban.
A human's body was made from Reiatsu Particles, and the soul was connected to it via a Chain of Fate.
When the soul left the body, it wasn't immediate death. If the chain remained intact, a Shinigami could treat the person, and they could return to life.
But if the Chain of Fate was broken, no healing could restore life — even if the soul re-entered the body.
This artifact, the Soul Chain, could repair the Chain of Fate and reconnect the soul to the body.
Meaning: as long as the body remained intact, it could resurrect the dead.
"This might be useful…" He stored it away.
He moved on to examine more Tenshihō Banshōban.
"Soulshock Gloves… forcibly eject the soul from the body…"
"Spirit Amulet… protects the soul… basically an ornamental version of Bakudō #39: Enkōsen, right?"
"Flesh Doll… lets a Shinigami possess a physical body?"
The Flesh Doll functioned like a prototype for the Gigai, which hadn't been invented yet.
It was a white humanoid figure with no facial features or distinguishing traits.
Nanatsuki decided to test it.
The Flesh Doll could only be used in the World of the Living — it didn't work in Soul Society.
Later, he took it to the real world.
Entering it, the surface began to shift — like melting clay.
Soon, the Flesh Doll had reshaped into Nanatsuki's exact form.
"Even the clothes I was wearing as a spirit showed up…"
He realized this doll was more than a simple decoy.
It could imitate the spirit's form down to clothing and hairstyle.
He cut his hand — inside was white material.
"It's still not the same as real flesh… Inferior to a Gigai."
Modern Artificial Bodies were indistinguishable from real human flesh.
Even Shiba Isshin had used one created by Urahara Kisuke to marry and have children.
The Flesh Doll wasn't that advanced — its transformation was only skin deep.
"The benefit is that anyone can use this. Artificial Bodies are custom-made."
He stored the doll. Until Artificial Bodies were widely available, the Flesh Doll could still prove useful.
Returning to the lab, Nanatsuki resumed organizing.
He soon found another intriguing object.
"Sosuke, this one suits your water-type Zanpakutō quite well!"
He tossed over a string of prayer beads.
Aizen caught them and immediately sensed embedded Kidō patterns.
"They've got water-creation and water-control spells embedded," Nanatsuki explained.
To him, it was minor, but for Aizen, who needed to mimic a water-type Zanpakutō, it was perfect.
"Control and create water, huh… This will be useful," Aizen said, putting them on.
Testing them, he found their power comparable to level 30–40 Kidō.
Even better, they didn't require incantation to release power equivalent to chanted Kidō.
Satisfied, he nodded. With this, he could mimic his fake Zanpakutō even better.
"Hollow Poison…"
Nanatsuki then found something he was more familiar with.
A vial of Hollow Poison — labeled as extracted from a Vasto Lorde-level Hollow.
Hollows that secreted toxins were rare, and from a Vasto Lorde, even rarer.
"A good thing we eliminated the Tsunayashiro clan early…"
Even with his current strength, Nanatsuki wouldn't be able to suppress Vasto Lorde-level Hollow Poison for long.
If the vice-captain-tier clan head had Enrakyōden and used this to ambush him, things could've gone badly.
But the Tsunayashiro had lost that chance.
Their clan head died never knowing someone could impersonate Tokinada and steal the family blade.
The rest of the relics were ornamental. Nanatsuki set them aside.
Next, he turned to the most important haul: Soul King Fragments sealed in jars.
Upon careful inspection, he realized these all came from the same leg — specifically, the lower leg.
The kneecap and skin were relatively whole, and the calf muscle was one piece, but the leg bones had been chopped into smaller chunks.
Each fragment was around one centimeter.
He opened a jar and removed one.
Suddenly, his shadow stirred.
Dark tendrils emerged within it, wrapping around the bone's shadow.
Moments later, the disturbance vanished — as if it were an illusion.
He glanced over at Aizen, who was still busy with the books and hadn't noticed.
The Soul King fragment still cast a shadow — but something inside that shadow had been drawn into Nanatsuki's own.
It was a piece of the Soul King's Shadow.
The amount in each bone was small, but he continued extracting until he had taken in every trace from the entire set.
Though each fragment was tiny, they added up to a sizable section of the leg.
With these absorbed, his mastery over shadows increased significantly.
The clearest improvement was in his Bankai's power.
Previously, he could summon two shadows at half his base power.
Now, after absorbing the Soul King's Shadow, his shadows had 60% of his power.
"That's a big boost…" he thought.
Three shadows with 60% of his strength each — and his shadows couldn't be injured like a real body.
To destroy them, you'd need to overwhelm them with Reiatsu.
Even if broken, the damage didn't carry over — only spiritual energy was lost.
"And I haven't absorbed the big ones yet!"
He turned to the final two fragments: the kneecap and calf muscle.
As he removed them, his shadow trembled again.
Dark tendrils wrapped around their shadows.
Suddenly, he felt a mental saturation — not hunger, but a spiritual fullness.
His shadow abilities had been enhanced drastically.
He returned the fragments to their containers and entered the training chamber next to the lab.
"Bankai — Shosō Eijin."
His Bankai activated, but instead of spreading outward, the shadow space remained hidden within his own shadow.
Then it began to grow and divide.
From a distance, it looked like black oil bubbling from a crack in the floor.
Three shadows emerged.
Three identical figures stood before him.
Now, he could summon three clones at 60% of his power each.
"And that's not all…"
With a thought, the shadows' shapes shifted.
They changed into three different figures.
Now, three female silhouettes stood before him: Katori Batsu'unsai, Azashiro Kana, and Shihoin Yoruichi.
"As long as I've summoned a shadow once, I can summon it again anytime. That means I can use three different powers simultaneously — four, if I count my own."
Nanatsuki's lips curled upward — he couldn't hide his joy.
His shadow abilities had undergone a massive breakthrough.
His Bankai could now not only mimic others' powers by summoning their shadows,
but do so three times at once.
A true evolution.
Back in the lab, Aizen was still arranging the bookshelf.
"Sosuke, let me help you," Nanatsuki said with a smile.
"Sensei, I've found some Kidō tomes."
He could tell his teacher was in high spirits — understandably so, given the results of their mission.
"Oh? Anything interesting?"
Nanatsuki wasn't surprised there were Kidō scrolls in the Tsunayashiro library.
Given their heritage, it was only natural they had amassed most of the standard sequences.
"There are plenty of high-level Kidō. Even Hadō #90: Kurohitsugi is in there. And some that aren't even part of the numbered catalog."
Aizen handed him a scroll.
"This one details spells to control Kōtotsu and Kōryū — it's what Tsunayashiro Tokinada tried to use to ambush Kakyō and Kana."
Nanatsuki flipped through it.
The clan had collected a vast archive — from low-tier to high-tier Kidō.
"Senju Kyōtentaihō… even stronger than Hiryū Gekizoku Shinten Raihō."
"Fanged Light Howl, Diamond Burst, Frostfang March…"
"They've gathered nearly as many high-level spells as the Kidō Corps."
Aizen nodded. "And lots of notes too. With those insights, learning will be much faster."
The clan's wealth of knowledge should have produced many gifted successors.
But in recent generations, they had neglected it.
The family had rotted.
When Nanatsuki and Aizen struck, only three members — including the clan head — had reached vice-captain level.
Once Enrakyōden was taken, they were powerless.