Without a signal from either, their centers of gravity leaned forward simultaneously.
Like leaping beasts, the two massive forms kicked off the ground at the same moment. The floor groaned, metal fragments drifted into the air, and the resulting wind pressure surged outward like a physical wave.
"—Hah!!"
Roselia’s voice rang out, spearheading the explosion of sound.
The entire floor trembled as a high-pitched shriek of metal-on-metal followed. The jet-black and gold prosthetics locked hands in a direct grapple. Steel and gears roared in place of muscle, emitting a grinding, agonizing creak. Their drive units flared with light, and the sheer heat warped the surrounding air.
"Tch... you’ve got plenty of output for a hunk of junk, I'll give you that..."
Roselia’s lips curled into a sneer.
Metal fingers interlocked with metal fingers; joints showered the area with sparks. In that instant, her legs sank slightly as cracks spiderwebbed across the floor beneath her.
"—Rrrrgh... hah!!!"
With a guttural shout, she stepped in.
In the blink of an eye, Roselia twisted her body while still gripping the opponent’s hands. She leapt into the air and drove both feet into the giant’s chest armor with a savage drop kick.
A dull, heavy impact followed.
The air burst, and metal fragments danced in the wake of the blow. The sheer force sent the black giant reeling—no, it did more than just push it back. The machine was blown away like a cannonball, slamming deep into a structural pillar.
Man, she’s really going all out.
Before the thought could even fully form in my mind, Roselia was already making her next move. Staring down the fallen giant, she kicked off the floor with everything she had. Cracks lengthened along her path, trailing the sparks flying from her metal boots.
"I bet you don't want to use your toys in here any more than I do!" she provoked, her voice sharp.
The black prosthetic pried itself out of the pillar with a slow, mechanical heave. Its entire outer shell groaned, and the internal servos let out a predatory whine.
Without a second's delay, Roselia dashed low, gouging the floor as she moved. She stayed just inches above the ground before launching a vicious, scooping uppercut.
The fist tore through the air.
But the opponent reacted. It twisted its body by a paper-thin margin, dodging the strike before using her own momentum to hammer down on her elbow.
"—!"
A dull thud echoed as her balance broke. Roselia’s frame was momentarily lifted off the ground.
In that split second, the black giant wound up its massive arm. Its fist snapped forward like a whip, making the air wail.
Bagon!
The roar shook the entire floor. A right straight like a falling anvil struck Roselia square in the back. The heavy resonance of metal colliding with reinforced chassis reached the very walls. Her body was sent flying, tumbling across the floor before sliding toward where I stood.
"—Hey, do you need a hand?" I called out.
Roselia looked up, wiping a streak of blood from the corner of her mouth with a single finger. She glared back at the enemy.
"...I don't!!"
A short, sharp refusal.
Her eyes were still burning. She steadied her ragged, beast-like breathing and forced herself back onto her feet.
I shook my head and sighed. Right, right. No unnecessary interference.
Roselia jerked her chin up in silence. In the next instant, a flash of electricity erupted from her back. As power lines surged, the seams of her chest armor bled a deep vermillion, and fine cracks began to spider across the metal surface.
A sound like a racing heartbeat echoed—faster and louder than before. Her movements shifted. The air itself felt thick and heavy, as if the gravity in the room had suddenly intensified.
The moment she kicked off, her drive system let out a deafening roar. She blurred, charging forward with the speed of a bullet. The black giant reacted, swinging its massive arm, but Roselia was no longer there.
Fists traced golden arcs through the air as the sounds of metal clashing against metal overlapped in a rapid-fire staccato. With every spark that scattered across the floor, her shadow seemed to blur and vanish.
She was reading the opponent’s center of gravity perfectly, striking before it could fall and punishing it before it could recover. Each punch accurately targeted the prosthetic’s drive shafts, carving permanent distortions into the enemy's frame. With every hit, metal groaned and sparks sprayed from the giant's internal mechanisms.
The black prosthetic’s movements stuttered for a fraction of a second. A cluster of sparks burst from its joints, and the roar of its servos turned into a ragged mess.
"Right here!" Roselia’s voice boomed.
Her arm snapped like a whip. A golden flash streaked through the air as the wind howled.
But then, the black prosthetic’s armor deployed from within. With a heavy clunk, the outer shell shifted and expanded, wrapping around the machine like a fortress.
Gagiin! An unpleasant, jarring sound filled the room.
Roselia’s fist was deflected. She tried to pull her arm back from the recoil, but she was too slow. The giant caught her.
"...Tch!"
The massive black hand clamped down on Roselia’s arm, and the screech of warping metal filled the air. Cracks radiated across the floor as Roselia’s arm began to buckle under the pressure.
—This is bad.
My hand instinctively went to my pistol, but in that moment, Roselia let out a sharp laugh.
"I’m not done yet!"
Her fingertips brushed the latch on her chest. It was a tiny, effortless motion.
The air burst. Inside her prosthetic, the output lines were instantly redistributed. A pale blue light raced through her body like glowing sinews, tracing the path of her artificial heart. Then, a series of satisfying clicks rang out in rapid succession.
After a heartbeat of silence, Roselia’s armor plates blew outward.
Shoulders, arms, legs, and the heavy shield on her back—the heavy armored parts detached and slammed into the floor. Metal bounced and sparks flew as if a rain of iron was pouring over the laboratory. The black giant was forced back by the sheer force of the purge, losing its grip on her arm.
Standing there was a version of Roselia that looked like a completely different person.
Having discarded her outer shell, her exposed prosthetic frame was much closer to a human silhouette. It was a series of supple lines and efficient, minimalist structures. Though it looked thin, every inch of it was acutely sharpened for performance. Her golden limbs gleamed under the facility lights.
"Let’s go."
She spoke quietly, her voice carrying a strange, eerie stillness. It was the calm before the storm.
Then—Roselia vanished.
The only thing visible was a trail of pale blue light. In her right hand, a plasma blade had been deployed before I could even see the motion. The blade's trajectory left a lingering afterglow that seemed to slice the very air.
Using every surface—walls, floor, ceiling—Roselia bounced through the room like a lightning bolt. It was a single, fluid flow, a dance of destruction. The black giant’s sensors couldn't keep up. Every time it tried to lock on, only afterimages tore through its field of vision.
Finally, the enemy stopped trying to track her and curled into a ball, bracing for the impact.
"...Clever. But useless."
Roselia’s voice echoed from directly behind the enemy.
The air hissed. Whish.
Following the sound, a streak of light remained in the air. A single trail of the pale blue blade drew a perfect arc, and Roselia’s hair fluttered upward in the draft. Red and blue intersected for a fleeting second, and the world seemed to stop.
Zuzun—
The black giant, split perfectly in two, crumbled under its own weight. Pieces of its armor clattered to the floor a second later, and a haze of heat rose from the wreckage.
Roselia let out a quiet, steady breath. She looked back over her shoulder at me, a small smirk playing on her lips.
"See? I told you I could be smart about it."
She deactivated the plasma blade as she spoke. The afterglow wafted through the air before settling on the floor. Standing considerably shorter than she had been minutes ago, she put her hands on her hips and gave a mischievous "Nihihi" laugh.
In the quiet of the night, the sharp scent of scorched metal drifted through the floor.