In the depths of Hollow Zero, after killing the newly discovered Ethereal Swarm, now dubbed Arachne. The members of Section 6 began their long trek out; their Bangboo, Agent Gulliver, it finished creating a carrot, marking the route out from Hollow Zero.
While making their way back, stray Ethereals lunged from the shadows, but the group cut through them with ease.
"So why do you call them Riders anyway?" Soukaku asked, swinging her metal banner in a wide arc that shattered an Ethereal into shards of black Ether.
"It's their legacy," Tsutsumi answered calmly, his Faiz Edge glowing red as he bisected another Ethereal. "They've all called themselves 'Kamen Riders.' The name goes back to the very first, Kamen Rider Ichigo."
"'Ichigo'?" Yanagi asked, slashing an Ethereal with her naginata. "Tell us more about him."
Tsutsumi didn't slow his pace. "He was a man captured by an evil organization and turned into a cyborg soldier. But instead of serving them, he broke free and used the power they gave him to destroy them."
Harumasa raised an eyebrow as he loosed a few arrows into another group. "So let me get this straight… they turned him into a weapon, and he turned that same power back on them?"
"Pretty much." Tsutsumi spun, kicking an Ethereal into Miyabi's path, as she cleaved it clean in half.
Yanagi smiled faintly. "Sounds like an old legend… or one of those ancient movies."
Tsutsumi caught the disbelief in her tone, but said nothing. To them, Riders probably did sound like fiction.
"Uhh, Chief?" Soukaku's voice cut through the calm. She lifted her Ether detector, its screen pulsing with red light and sharp beeps. "The Ether levels are spiking."
Miyabi's expression tightened. "So… she's here."
The others followed her gaze as Tsutsumi looked off into the distance. Between the skeletal ruins, something red and white unfurled, like the petals of a colossal flower opening in slow motion.
A figure rose from its center.
She was legless, floating gracefully above the broken ground. Her body shimmered with both beauty and dread, a woman's form draped in a flowing gown of white silk, streaked with crimson. Her Core head tilted as if listening to the world's heartbeat. Around her, swarms of insect-like Ethereals hovered, their wings humming and stingers glowing.
Tsutsumi raised his camera, snapping a photo. "What… is that?"
"Nineveh, another Ethereal Swarm like the Arachne we just fought not that long ago." Yanagi explained calmly, seeing that although Tsutsumi is really strong, he is still inexperienced and still has much to learn about this world.
Before anyone could react, Miyabi took off, her haori flaring behind her as she sprinted toward Nineveh.
"Chief, wait!" Yanagi started, but her shout was cut off by a familiar announcement.
Attack Ride: Agito Tornador!
The red and yellow hoverbike appeared beside Tsutsumi, and before any of the other members from Section 6 could even ask, he drove off on it, also heading directly toward Nineveh.
Yanagi stood there for a beat, speechless. "…Didn't she just scold him for that exact thing?"
Just a couple of minutes ago, Miyabi was scolding Tsutsumi for running off and fighting an Ethereal Swarm alone; now he is at it again. And the irony was that Miyabi was also doing it, running off to fight Nineveh alone.
Harumasa chuckled. "You sure he's adopted?"
"Now's not the time." Yanagi sighed, taking charge. "Move! We're not letting them face Nineveh alone!"
The group quickly tries and follow the two, but they were both moving too fast for them to simply catch up.
Far ahead, at a distance.
"Watch out!"
A petite white-haired girl cried out as a hornet-like Ethereal dived toward her companion and a small Bangboo unit. The insect's stinger glowed an ominous yellow as it prepared to strike.
A blue flash sliced through the air.
The Ethereal exploded into shards, scattering across the cracked pavement. Behind them, Miyabi stood, blade half-drawn, her long black hair fluttering in the wind. She sheathed her sword with a sharp click and darted past them without a word, chasing the distant glow of red and white.
"W-Who was that?" the Bangboo stammered.
Before its partner could answer, a roar of engines screamed overhead.
A yellow-red blur on a hoverbike streaked past.
The red-suited robot's eyes widened, equally dumbfounded. "Is that... Is that a freaking hoverbike!?"
The little Bangboo beside him nodded. "I think… it was."
As Miyabi and the Rider vanished into the distance, the other from Section 6 finally arrived at the scene from the same direction they had come.
...
"Requisition?" The woman repeated, her brow furrowing. She was an investigator, still catching her breath after being saved by Miyabi not long ago.
"That's right," Yanagi replied, her tone clipped and professional. "This Bangboo from the Academy, I need it to continue guiding us deeper for the upcoming operation."
Agent Gulliver [Carrot] had been programmed only to lead them out of Hollow Zero, not further in. Recalculating and building a new navigation path would take too long, and by then, the two fox Thirens would be too deep to track.
The members of Section 6 weren't worried about those two losing a fight. They were worried about them getting lost.
Yanagi's sharp gaze swept over the group accompanying the investigator: a Bangboo named Eous, and a trio from Cunning Hares, all present and clearly nervous.
"The targets have deviated from the projected path," Yanagi continued crisply. "We require the Bangboo with the 'Carrot' data for navigation. This is an emergency requisition of critical assets."
To her, Eous was simply a pilot Bangboo from the White Star Institute. She didn't bother with pleasantries.
Harumasa stepped up beside her, smiling faintly to smooth the edges of her words."In simpler terms," he said, "if any of your gear gets damaged, we'll handle compensation."
"Mm-hmm?!" Eous replied in a burst of digital chatter, tone rising in comical surprise.
"Don't worry, little guy!" Soukaku grinned, placing both hands on her hips. "I'll protect you!"
"Hmm... since you're with the Hollow Special Operations..." The investigator hesitated, glancing between the disciplined Section 6 agents and the scrappy trio behind her.
She assumed Eous was an official Academy asset and that the Cunning Hares were a legitimate research team. She didn't realize that the Cunning Hares were anything but official, a small-time dispatch agency that would take nearly any job if the pay was right.
Their freelance work often walked the thin line between "independent contracting" and "illegal entry." And their companion, Eous, was worse: a Proxy, a remotely controlled Bangboo used by someone outside the Hollow.
In short, none of them were supposed to be here. If caught, all of them could be arrested the moment they set foot outside Hollow Zero.
After all, this was the first Hollow, classified, dangerous, and tightly regulated. You didn't just stroll in and out of it.
Just as the investigator was about to approve the requisition, the Cunning Hares started fidgeting.
"Hey, Nicole, maybe we should... y'know, rescue the store manager and get out of here?" Billy, the red robot, whispered frantically to his boss, a pink-haired woman with twin tails.
Going on a mission with special ops to face a super-sized Ethereal, with the risk of damage involved, just thinking about it was terrifying!
Nicole nodded in full agreement. She promptly explained Eous's true affiliation to the Hollow Special Operations and made it clear they needed to reconsider.
The three of them and Eous soon huddled to the side.
"Store manager, what do we do?" After 'rescuing' Eous, Billy leaned in and asked quietly.
"That Ethereal's huge... and it flies," Anby, the small white-haired girl, said.
"Our assessment is done. There's no harm in turning them down." Nicole said sharply. "It's private property, they can't just take it."
Her expression was tense, but her meaning was obvious.
Retreat. Retreat. Absolutely retreat.
"I'm with Nicole on this one," Billy added, nodding like his head might pop off.
Anby stayed quiet, gaze resting on Eous. When the little Bangboo didn't move, she knew what that meant. Proxy was thinking. And when Proxy was thinking... then it meant they weren't planning on backing down.
Eous's lenses flickered as it turned toward the distance. The Rider and the woman were long gone, but high above, a faint red glimmer still moved, that was Nineveh.
The Bangboo's voice came, steady and measured.
"These agents have skill. They can keep us alive. I'll only handle navigation. Refusing might... complicate things."
Nicole exhaled slowly. She didn't like it, but she trusted Proxy's judgment more than her own gut.
"Fine," she muttered. "We'll go along. But if anything breaks, the bill's on your department."
Harumasa just nodded. "Fair."
Anby gave a silent nod too, while Billy... perked up immediately.
"So uh, does that mean... you'll also cover my ammo expenses?"
Tsukishiro Yanagi turned toward him with the faintest smirk, a look that said she'd dealt with this kind before.
"Of course."
Billy practically lit up, bouncing on his heels. "Best. Mission. Ever!"
With the arrangements settled, both sides moved out immediately under Eous's lead.
...
A hazy afterglow pierced the thick cloud cover above, scattering light through the breaks like golden spears from heaven. Each ray shimmered against the drifting debris, gilding the floating ruins in ethereal gold. Some hung motionless, others drifted slowly, fragments of a city that had long defied gravity and time.
"Still no sign?" Harumasa shouted, sprinting full tilt. His breath came out ragged, but his eyes remained sharp. Yanagi and Soukaku flanked him, their boots thudding in rhythm against the cracked ground.
Behind them, Eous scampered with all its strength, tiny legs pumping furiously, its round body tilting backward from sheer wind resistance.
Nicole and Billy followed not far behind, both visibly suffering.
"Nicole... what the hell is that girl?! She's tiny, holding a massive weapon, and she's running faster than anyone!" Billy gasped, eyes bulging as he stared at Soukaku's figure ahead. The tiny girl was holding a massive steel banner, yet running faster than most vehicles.
"You're asking me?" Nicole barked between breaths, stumbling slightly. "I'm dying over here!"
Her voice cracked with fatigue. This whole trip had been a relentless blur of running, jumping, and fighting, a chaotic ballet through collapsing ruins and Ethereal attacks. Not a single moment to breathe.
Her lungs burned. Her muscles screamed. Her will was the only thing keeping her upright.
Up ahead, Harumasa slowed just long enough to squint toward a distant ledge, even his breathing hitching.
"There! That way!" He pointed toward a stretch of floating ruin, where a blur of motion streaked across the platforms with inhuman speed.
In that instant, Miyabi had shut out the world. Her focus was razor-sharp, her eyes locked on one target: Nineveh.
Her blade gleamed as she darted between the ruins, cutting through Ethereals like they were made of mist. The air rippled behind her strikes, traces of Ether scattering like silver petals.
She didn't slow. The path was already mapped in her head, the angle of Nineveh's flight, the probable descent arc, the ledge she'd reach in exactly three seconds.
A pulse of elemental energy coursed from her drone, lighting the edge of her blade in radiant white-blue. She leapt, twisting through the air, and struck.
The shockwave rippled outward. Nineveh reeled, its haunting scream echoing like a chorus of voices in pain. It rose, massive and weightless, trailing ribbons of Etheric mist as it ascended out of reach.
Then...
Final Attack Ride:
The mechanical voice resonated through the air. The sudden announcement drew Miyabi's eyes upward.
From above, the sky split open into a swirl of glowing yellow. A roll of oversized cards unfolded in the air, forming a luminous path.
Through them, Tsutsumi descended.
Each time he passed through a card, a new sigil flared, light bending, folding, accelerating him further. His silhouette became a streak of magenta, a meteor in human form.
Nineveh sensed the danger and veered to the side, crimson wings fanning out like silk. But the cards shifted instantly, expanding and locking onto her trajectory.
De-De-De-Decade!
The impact hit like thunder. A shockwave burst outward, tearing through the clouds. The Rider's kick slammed into Nineveh's back, detonating a cascade of explosions that lit up the sky.
The colossal Ethereal tumbled from the heavens, trailing burning light as it fell, a fallen star crashing toward the nearby skyscraper ruin.
Everyone froze. Even the battle-hardened members of Section 6 stood in stunned silence.
The investigator uttered. "Did... did he just kick an Ethereal out of the sky?"
Tsutsumi landed on the ground in front of the ruined building where Nineveh as just crashed into.
Miyabi landed beside her son. She opened her mouth, ready to scold him for recklessly diving into yet another fight against an Ethereal Swarm, but froze when she felt the air shift.
A piercing shriek filled the ruins.
Nineveh's form rose again, its once-beautiful shape now distorted, enraged. Shattered fragments of its shell hovered around it like petals of molten glass, glowing with raw Ether.
Both Tsutsumi and Miyabi instinctively broke into a sprint, ready to charge again, but before either could even begin, the massive Ethereal stirred.
Nineveh's upper body twisted at an impossible angle, her long ribbons of light curling inward like the petals of a dying flower. The glow of her core flickered, then deepened into a dark, blood-red hue.
And then, a voice.
"Damn you... Ice fox... Damn you... Decade..."
The sound was warped, fractured between layers of human pain and mechanical distortion. It rippled through the ruins like a haunting echo, pressing down on everyone who heard it.
"I'll remember... this..."
Even the air seemed to tighten for a moment.
Yanagi and the others froze mid-motion, eyes wide. No Ethereal should have been able to speak. Even Miyabi was caught off guard by this.
Tsutsumi, who didn't know that Ethereal can't speak, continued to chase after her, planning to finish her off.
But before he could take another step, thick vines of crystallized Ether burst from the shattered ground, slamming into the ruins around him and blocking his path.
More movement followed, dozens of insect-like Ethereals swarming down from above, their wings shrieking as they dove toward him.
Both mother and son drew their swords and made quick work of the Ethereals that surrounded them. Blue and magenta spirit-flames dance beside one another before fading away as the last Ethereal dropped dead on the ground, its body fading away into Ether particles.
They both turned their eyes upward.
The sky above was already closing, and Nineveh has already disappeared into the heavy clouds.