The Underground Bunker

Night had just fallen over Tokyo. The moon had only begun to rise on the horizon, and the neon lights of the city’s heart flickered to life in a chaotic sprawl. Flapping her pitch-black wings, the yokai Yosuzume soared high above the bustling streets. In her hands, she gripped a blade stolen from the Nura residence.

While the young lord of the Nura Clan led most of the household yokai out to face the enemy, Yosuzume had used her abilities to infiltrate the poorly defended mansion. She had stolen the demon-slaying blade, a treasure passed down through three generations of the Nura line, before making a swift escape. At this very moment, the young lord had only just arrived at the battlefield with his Night Parade, and the chaotic skirmish with the yokai of Shikoku was about to begin.

Soaring through the cold winds above the city, Yosuzume flew toward the outskirts at high speed. The city’s neon lights transformed into a flowing river of light beneath her as she quickly distanced herself from the city center, heading toward the desolate countryside. As the lights below grew sparse, Yosuzume moved further from the noisy metropolis. The dense buildings were gradually replaced by lush, forested mountains. Amidst the fading light, she left the main district and entered the barren mountain ranges.

Looking down at the dark mountains below, Yosuzume began to descend. She eventually landed in a wild forest of tall, flourishing trees, stepping onto a patch of overgrown weeds.

Standing in the wilderness, Yosuzume glanced around. She then raised the blade in her hand and called out in a low voice.

"I have arrived. Come forth, Minamoto Gorozaemon."

"Heh, heh, heh... As expected of a shikigami from that lord's family. You certainly work efficiently." With a strange, high-pitched cackle, a hunched, elderly figure emerged slowly from behind a tall tree.

It was a deformed old yokai. He was short, with a white beard, wearing long yellow robes and leaning on a walking stick. His head was unnaturally elongated and misshapen, and upon it sat a single, bulging red eye that darted about erratically. He looked at Yosuzume with a smile that oozed malice.

"I thought you would have to tangle with the Nura yokai for quite a while to get this thing out. I didn't expect it to be so fast," Minamoto Gorozaemon said with a snicker. Yosuzume answered directly.

"I intentionally leaked information about Tamazuki's location to the Nura Clan. The young lord took the vast majority of their power to subjugate him. The Nura residence was empty, and with my abilities, it was easy to succeed," Yosuzume said slowly. Listening to her, Minamoto Gorozaemon’s expression remained unchanged, his dark grin deepening.

"Heh... Tamazuki. A little tanuki born with ambition but into the wrong era. With just a little guidance, he becomes a pawn to be moved at will. Inugami Gyobu Tanuki truly sired a 'good son.' Having a fellow like him around saves us a lot of trouble."

"Has the young lord of the Nura Clan already taken his Night Parade to find that little tanuki from Shikoku? I'm curious. What will the result of their duel be? I’m looking forward to seeing the sole heir of Nura Rihyon and his Night Parade be swallowed by the Devil King's Mallet. After losing his son, he will lose his grandson, and the culprit will be the son of his former close friend. I wonder if that old dog Nura Rihyon will commit suicide out of despair? Heh, heh, heh."

Minamoto Gorozaemon spoke with a poisonous tone. Yosuzume remained silent as she watched him turn and walk toward the depths of the dense forest.

"Let's go, little shikigami. It is time to attend to our true business."

Watching Minamoto Gorozaemon slip into the shadows, Yosuzume tightened her grip on the blade and followed closely behind.

Led by Minamoto Gorozaemon, Yosuzume trekked through the dense mountain forest, moving quickly across the complex terrain. Along the way, several objects emerging from the weeds caught her eye. Looking closely, she saw many rusted empty oil drums, broken and overturned concrete posts, and even barbed wire bristling with sharp spikes. Clearly, there were traces of human activity here, though it seemed to have been a long time ago.

Minamoto Gorozaemon continued forward. The deeper they went, the more artificial remains appeared. Besides the stone posts, wire, and oil drums, there were piles of sandbags, collapsed wooden towers, and bunkers made entirely of concrete, now covered in moss. Clear cracks were visible on these concrete bunkers, along with distinct claw marks.

Finally, Minamoto Gorozaemon stopped before a cliffside. Embedded in the rock was a massive, rusted iron gate. The door panels had long since vanished, and countless vines and moss climbed across the portal eroded by time. At that moment, Yosuzume noticed something etched into the iron frame. Upon closer inspection, she realized it was the Five-pointed Kikyo Seal.

"Let's head down."

Minamoto Gorozaemon looked back at the startled Yosuzume and spoke bluntly. He then led the way into the darkness beyond the iron gate, and Yosuzume followed.

There was not a single spark of light beyond the gate. Fortunately, Yosuzume relied on her yokai night vision to see her surroundings clearly. She discovered that behind the door was a man-made tunnel. The brick walls were laid out neatly in a rectangular shape, and a staircase led down into the deeper darkness. Following Minamoto Gorozaemon, Yosuzume descended. As she looked around, she saw patches of dark red splashed across the dark tunnel walls. As a yokai, she could tell that these were stains of dried blood, and some even emitted a faint demonic energy.

"Where... exactly is this place?" Yosuzume finally couldn't help but ask. Hearing her, Minamoto Gorozaemon glanced back at her and responded with a dark chuckle.

"Oh? You didn't know? Well, that’s understandable. After all, you’re just a shikigami. Your master has no need to explain everything to you clearly."

Minamoto Gorozaemon turned his gaze back to the darkness ahead and continued slowly.

"Very well, I shall explain it to you briefly. This is an underground bunker built by humans during the Great War to hide from those man-made iron birds."

"An underground bunker built by humans during the Great War? But why are there so many traces of yokai in here? And why was there a mark of Onmyojutsu on the gate earlier?" Yosuzume pressed. Minamoto Gorozaemon answered leisurely.

"Why are there yokai and Onmyojutsu marks? Heh, heh, heh... It's quite simple. This underground bunker wasn't built for any military purpose. It was made as a safe place to secretly conduct research into forbidden Onmyojutsu. There are many such bunkers around Tokyo. In the latter stages of the Great War, the research results from these places were applied to the battlefield, causing casualties far greater than what we yokai could ever achieve." Minamoto Gorozaemon paused to think for a moment, then summarized, "You can think of it as a workshop. A workshop for creating techniques used for war and killing."

"A workshop... Humans using spells to slaughter one another?" Yosuzume remarked in surprise. Minamoto Gorozaemon followed with a wicked grin.

"Indeed. For thousands of years, Onmyojutsu has been used to subjugate the creatures of the demon realm. Traditional Onmyojutsu rarely targeted humans or armies, making it difficult to meet the demands of war."

"During the Meiji era, the human government dissolved the original Onmyoryo to control the Onmyodo that had been held by those great clans for so long. By winning over small families and branch houses, they fragmented the social hierarchy of the great clans and established the Imperial Onmyo Academy. While isolating the upper-class traditional families, they gathered a vast amount of spellcasting power from across the nation."

"During the war, the human high command ordered the Imperial Onmyo Academy to conduct extensive research on techniques for warfare, turning them into weapons for the battlefield. Toward the end of the war, because of the air raids from the iron birds, the Academy's research moved underground. That is how these bunkers came to be," Minamoto Gorozaemon said slowly. Yosuzume paused for a moment, then spoke.

"Humans... are truly madness incarnate when they slaughter each other." As she spoke, she looked at the dark bloodstains on a wall. Sensing the faint demonic energy, she asked again, "Then what is the deal with all this demonic energy? Are they the shikigami of the Onmyoji who conducted the research?"

"No, they weren't shikigami..." Minamoto Gorozaemon continued in the same tone.

"You’ve already noticed, haven't you? There are many residues of demonic blood in this tunnel, all left behind by yokai. Those yokai attacked this Onmyo bunker and engaged in a fierce fight to the death with the garrison. In the end, the yokai seized this bunker, and both sides suffered heavy casualties here."

Listening to him, Yosuzume was stunned. She spoke with disbelief, "Yokai? Yokai attacking a human Onmyo bunker during the war? Which yokai would be so bold?" There was clear astonishment in her voice. A militarized Onmyoji bunker was not something a common yokai could easily shake. Minamoto Gorozaemon gave a dark laugh.

"Heh, heh. In this Tokyo, from ancient times to the present, who else but the Nura Clan would have such courage and power?"

"The Nura Clan? The yokai who attacked this place belonged to the Nura Clan? Why did they attack?" Yosuzume was surprised. Minamoto Gorozaemon continued in a heavy voice.

"The Onmyo military of the Imperial Onmyo Academy once invaded the demon realm on a large scale, wanting to conquer it and bring it under the rule of the human empire. As the overseers of the Tokyo demon realm, the Nura Clan was their primary target. Long ago, the Onmyojutsu researched by the Academy became increasingly inhumane and dangerous. With the support of Inari behind the scenes... in short, the conflict between Nura and the Imperial Onmyo Academy was extremely sharp at that time. Their confrontation lasted for decades, and this was one of the battlefields formed when that conflict finally exploded."

"A battlefield?"

"Correct. The head of the Nura Clan at the time, the son of Rihyon, Nura Rihan, took that very sword in your hand and led his Night Parade to slaughter their way in here. They nearly wiped out the entire garrison, forcibly ending the research inside."

Listening to his words, Yosuzume was dazed. She looked down at the demon-slaying blade, Nenekirimaru, which radiated a chilling aura in her hands.

"Nura Rihan led his Night Parade to purge this place... But Minamoto Gorozaemon, what exactly are we doing here? And why bring Nura Rihan's personal blade?" Yosuzume looked at him again. Minamoto Gorozaemon continued to grin.

"We are here to find an ally."

"An ally?"

"Indeed. The enemy of our enemy is our ally. After a fellow who has such a grudge against the Nura Clan wakes up, what kind of vengeance will he unleash?"