Rise of the F-Rank Hero-Chapter 155: Floor 45

Miles below, in the crushing dark.

Oliver sat on the rocky shore of the subterranean lake, wringing out his coat. The water was freezing, sapping his body heat rapidly.

Around him, the darkness felt heavy, like a physical weight. The red eyes in the distance blinked and shifted, circling closer.

He was alone. No healer. No tank. No damage dealer.

Just him and his daggers.

"Sigh," Oliver exhaled, seeing his breath fog in the air. "This is going to be a pain without backup."

He reached up to his neck.

Clamped onto the collar of his coat was a silver brooch shaped like a feather. It was intricate, beautiful, and completely out of place on his rugged gear.

He tapped it twice.

"Wake up, Sera," Oliver whispered. "Nap time is over."

Hummmm.

A low, mechanical vibration resonated from the brooch.

"System reboot sequence initiated," a tiny, synthesized voice spoke from the silver feather. "Mana reserves: 98%. Sleep Mode: Disengaged."

The brooch didn’t just detach. It liquefied.

Like mercury, the silver metal flowed off his collar, dripping onto the rocky ground. It pooled there for a second, glowing with a soft blue light, before rapidly expanding.

Whirrr-Click-Snap.

The liquid metal grew bones. It wove synthetic muscles. It formed skin that looked perfectly, indistinguishably human.

In three seconds, the puddle was gone.

Standing before Oliver was Seraphine.

She was dressed in her usual maid outfit—generated by her chassis—looking pristine and dry in the damp cavern. Her silver hair was tied back in a neat bun. Her blue eyes flickered as her HUD initialized. 𝗳𝚛𝗲𝕖𝚠𝚎𝚋𝗻𝗼𝕧𝗲𝐥.𝚌𝚘𝐦

"Boot sequence complete," Seraphine said, her voice monotone but clear.

She swiveled her head, scanning the environment. Her eyes glowed faintly as she switched to night vision.

"Location: Unknown subterranean strata. Mana density: Critical. Ambient temperature: 4 degrees Celsius."

She looked at Oliver, then scanned the empty space around him.

"Query: Where are Unit Amy and Unit Isolde?"

"Upstairs," Oliver said, standing up and rolling his shoulders. "We got separated. It’s just us, Sera."

Seraphine paused. Her internal processors whirred.

"Conclusion: Master is unaccompanied in a hostile environment."

SHING.

Her arms shifted. The skin on her forearms split open, revealing gleaming, high-frequency vibro-blades. Her eyes shifted from a soft blue to a combat-ready red.

"Combat Protocol: Alpha," Seraphine stated, stepping in front of Oliver to shield him from the darkness. "Directive: Eradicate all threats to Master."

From the shadows, a massive, reptilian beast lunged—a Cave Drake.

"Target acquired," Seraphine said.

She vanished.

Slash.

The Drake’s head slid off its neck before it even realized it was dead.

Seraphine flicked the blood off her arm-blade and turned back to Oliver.

"Orders, Master?"

Oliver smirked, drawing his daggers.

"What else. We stall here till they come down"

"Stall?" Seraphine tilted her head, her servos making a faint whirring sound. "Analysis: Static defense in a hostile zone increases the probability of encirclement by 400%. Tactical recommendation: Evasion and ascension."

"No," Oliver said, sheathing his dagger and looking up at the jagged, bioluminescent ceiling. "If I try to find the stairs up, I might take a wrong turn in this maze. We could miss them entirely. But Isolde..."

He tapped his chest, right where his heart was.

"She can track my mana signature.

They’ll come here. We just need to make sure we’re still breathing when they arrive."

He kicked the severed head of the Cave Drake toward the water.

"Besides, if we make enough noise, the monsters will come to us. Less walking for me."

Seraphine’s eyes flashed red as she processed the logic.

"Acknowledged. Strategy update: Fortress Protocol. We will hold this position until reinforcements arrive."

She turned to face the darkness of the cavern.

"I shall prepare the perimeter."

****

Stalling on Floor 45 wasn’t about sitting around and singing campfire songs. It was about slaughter.

The Abyssal Garden was a dense jungle of giant fungi and wet, slick rocks. And it was teeming with life that wanted to eat them.

Within ten minutes, the first wave hit.

Abyssal Stalkers. Pale, eyeless humanoids with long, serrated limbs that moved like spiders.

Skitter. Skitter. HISS.

Dozens of them poured over the rocks, sensing the fresh meat.

"Hostiles detected," Seraphine droned. "Count: 34. Threat Level: Moderate."

"Save mana," Oliver ordered, crouching low. "Physical only."

"Affirmative."

Seraphine moved. She didn’t run; she glided. Her feet were equipped with gravity-dampeners, allowing her to skate across the uneven terrain.

She met the first wave of Stalkers like a blender meeting fruit.

ZZZT-SLASH.

Her vibro-blades hummed at a frequency that shattered bone on impact. She spun in a whirlwind of steel, severing limbs and heads with surgical precision. She didn’t dodge; she calculated the trajectory of every claw and moved just enough to let it miss by a millimeter.

Oliver was the shadow to her light.

While Seraphine drew their attention with her flashy, spinning attacks, Oliver weaved through the chaos. He didn’t hack and slash. He punctured.

He slid under a Stalker, driving his dagger into its spine. He vaulted over another, slitting its throat.

"Behind you, Master," Seraphine stated calmly, decapitating a Stalker that had lunged at Oliver’s back.

"I know," Oliver grunted, kicking a monster into the water. "Thanks, Sera."

"Gratitude unnecessary. It is my primary function."

****

An hour later, the shore was littered with corpses. The water of the lake had turned a murky black-red from the blood.

The attacks had paused. The local predators had realized that the two small figures on the beach were not prey, but apex predators.

Oliver sat on a flat rock, shivering.

The adrenaline had worn off, and the freezing temperature of the floor was biting deep. His coat was still soaked, and there was no dry wood here to start a fire.

"Hypothermia imminent," Seraphine stated, standing over him. She was spotless, thanks to her self-cleaning nanite coating. "Master’s core body temperature has dropped to 35.8 degrees. Motor functions are compromising."

"I’m fine," Oliver chatted, hugging his knees. "Just... wish Amy was here. She makes a great space heater."

Seraphine’s eyes narrowed slightly. The aperture of her pupils contracted.

"Unit Amy is inefficient. She radiates heat indiscriminately, wasting energy."

Seraphine stepped closer.

"I possess internal thermal regulation coils powered by my mana core. I can adjust my surface temperature to optimal human survival levels."

She sat down on the rock next to him. She didn’t ask. She simply pulled Oliver into her lap.

"Whoa, Sera—"

"Do not struggle. You are shivering."

She wrapped her arms around him. Her skin, usually cool and synthetic, suddenly flared with a comforting, intense heat. It was like hugging a radiator wrapped in silk.

"Generating 40 degrees Celsius," Seraphine droned. "Initiating rapid warming sequence."

Oliver sighed, his muscles relaxing as the warmth seeped into his frozen bones. He rested his head on her shoulder—which was surprisingly soft, despite the metal chassis underneath.

"Better?" she asked, her voice uncharacteristically soft.

"Much," Oliver mumbled, his eyes heavy. "Thanks, Sera. You’re a lifesaver."

"Correction," she said, resting her chin on top of his head. "I am a multi-purpose combat and utility android. Saving your life is merely Sub-routine 1."

She paused, her hand moving up to stroke his wet hair mechanically. The rhythm was precise, mathematical, yet undeniably soothing.

"Sleep, Master. I will maintain the perimeter."

Oliver didn’t argue. The warmth of her chassis lulled him into a dreamless black.

****

When Oliver woke, his stiffness was gone. Seraphine had already disengaged, standing by the shoreline in full combat readiness, scanning the dark water.

"Status: Rest cycle complete," she announced without turning. "Stamina restored to 85%."

Oliver stood up, stretching his back until it cracked. He felt better. Stronger. But as he looked out over the subterranean lake, a strange sensation pricked at the back of his neck.

It wasn’t a sound. It wasn’t a smell. It was a... pull.

The black water, still as glass, seemed to be vibrating.

"Sera," Oliver whispered, stepping closer to the edge. "Do you sense something weird from the lake? A mana signature? A trap?"

Seraphine’s eyes glowed blue as she initiated a deep scan. She swept her gaze across the surface, then focused on the depths.

"Scan complete," she stated flatly. "Negative. Water composition is standard subterranean runoff. No biological or magical anomalies detected within a 500-meter radius."

"Nothing?" Oliver frowned.

"Affirmative. It is merely water."

Oliver nodded, turning away to check his daggers. ’Just nerves,’ he told himself. ’The fall scrambled my senses.’

But his gaze kept drifting back.

It was gnawing at him. A low, hum that resonated in his bones. It felt like the lake was whispering his name. It was the instinct of a scavenger—the gut feeling that had kept him alive for ten years in a world that wanted him dead.

’Trust the gut,’ Oliver thought. ’The machine sees data. I see opportunity.’

He dropped his daggers on the shore.

"Stay here, Sera. Guard my gear."

"Query: Master, entering unknown bodies of liquid is ill-advised without—"

SPLASH!

Oliver didn’t wait for the lecture. He broke the surface in a clean dive.