System Mission: Seduce the Strongest S-Class Hunters or Die Trying!-Chapter 131: [WHAT WAS LEFT BEHIND]

For a moment, Kairo could only stare. Everything around them—the wet drag of the monster’s limbs above, the hiss of falling grit from the ceiling—blurred into white noise.

The words had been clear. Too clear. They cut through Eli’s ruined voice like a blade.

"Use my blood, Kairo."

’Is he being serious right now?’

Shock crawled down his spine like ice. His black eyes narrowed, locking on the trembling figure in his arms as if the boy might vanish if he blinked.

Blood clung to Eli’s lips in dark streaks, ran in thin trails down his throat, dampened his torn clothes. His skin was pale and clammy, every tremor in his body obvious against Kairo’s hold—yet his yellow gaze still burned faintly through the haze, stubborn, alive.

Kairo’s pulse ticked once, hard. Only one question came out, clipped and low, almost against his will.

"...Are you suicidal?"

The question slipped before Kairo could stop it, more thought than speech, sharp but strangely absentminded—like his mind hadn’t caught up to his tongue.

Eli’s gaze widened. His lips parted, disbelief flickering across his face before his chest heaved with a broken laugh that cracked halfway out. "What—? No! I already told you!"

His voice splintered, raw with blood and exhaustion. "I’m not—I don’t want to die." His head shook weakly against Kairo’s shoulder, more blood dripping down his chin, warm against Kairo’s arm. "If anything—I want to live. I’ll do anything to live."

The words hit sharper than they should have, like a blow under Kairo’s ribs.

But the memory surfaced anyway—unbidden, unwanted.Eli’s mother, Elois, her voice fractured in the sterile air of a hospital room, crying against the rails of a bed. Kairo had been passing by, had heard without meaning to, her low broken words about her son repeatedly pushing himself to the edge. About not knowing how much more she could take.

His jaw clenched, the faintest crack running through his usually blank composure.

"You’re smaller than me. Paler." His voice cut hard, refined, almost clinical—anything to keep the weight from bleeding into his tone. "I produce more blood than the average person. You don’t. I can afford it. You can’t."

Eli’s lips moved, but no sound came out at first; his throat was too torn. He tried again, but Kairo’s voice pressed over his, sharp and commanding, each word like a strike.

"You’re already having headaches, aren’t you? Danger sense overloading you?" His black gaze dropped to the crimson running thick from Eli’s ears and nose, the tremor in his fingers as he clutched at Kairo’s sleeve like a lifeline.

"Don’t even think—"

"DANGER!"

The scream tore through the cavern, cutting Kairo off mid-sentence.

Eli’s body jolted violently in his grip, every nerve screaming as his yellow eyes flared wide.

His arm shot upward with trembling force, finger stabbing at the ceiling. "Kairo—above! Four of them—! Two toward Mio and Zaira, and then two toward us!"

Kairo didn’t hesitate. He never did.

His head snapped up, black eyes narrowing just as the air split with a wet, grotesque crack.

Four tentacles.

They writhed downward like living pillars of flesh, their bulk shredding through the air with sickening speed.

Two barreled toward Mio and Zaira, water exploding upward as the cavern groaned under the weight of their fall.

The other two coiled tighter, precise and merciless, aimed straight for him and Eli.

His muscles coiled on instinct. Blood hissed from the cut on his wrist, scarlet aura flaring sharp and bright as his veins sang with pressure. No blade? No problem.

He would not falter.

"Don’t worry about us, Captain—I got it!"

Mio’s voice snapped across the chaos, steadier now, cutting through the cacophony.

His body lurched forward at the same moment Kairo moved—threads bursting outward in arcs of silver, snapping like whips toward the limbs descending on Zaira.

His expression was still pale, sweat shining on his jaw, but his movements were crisp, precise again.

Like how he normally was.

’Good. He’s fully back with us.’

Kairo bent his knees, aura bursting in a violent flare as he shoved off the jagged stone.

The impact cracked the ground under his boots, dust exploding upward as he launched himself into motion.

Eli clung to him, weight tucked against his chest as Kairo twisted midair, narrowly clearing the descent.

The tentacle crashed down where they had been an instant before.

The impact was thunder.

Stone split, cracks spiderwebbing outward in violent bursts as shards rocketed through the cavern like jagged shrapnel.

Water geysered upward from the impact, spraying across Kairo’s face and hair as the ground quaked beneath them.

The cavern was chaos—stone screaming, water thrashing, silver threads slicing through the air like lightning. Every sound collided into a deafening storm, the shrieks of monster and man entwined.

And then—Eli’s voice again.

"—Mel!"

Kairo’s head snapped up.

From the ceiling, a shadow shifted—thick, writhing, alive. A fifth tentacle slid down, grotesque and deliberate, its slick mass glistening like a spear of flesh descending from the dark.

Not aimed at him. Not at Zaira.

At Mel.

Unconscious. Defenseless. Still sprawled across jagged stone, his chest barely rising, breath shallow and weak.

Kairo’s chest tightened, a flicker of something hot tearing through the iron calm in his face.

"Fuck." The curse broke from his throat, raw, sharp, as his grip on Eli tightened. Scarlet aura flared around him in violent arcs, bleeding across the cavern walls like a storm of light.

The monster wasn’t just lashing blindly anymore. It was calculating. Splitting them apart. Testing their limits.

Too far.

Too fast.

One captain. Three fronts.

The blood dripping from his wrist vibrated in response to his heartbeat, crimson droplets pulsing like they wanted to be shaped, to be used. He had enough for one burst.

Two, if he pushed.

But not enough for everything.

"Kairo—!" Eli’s trembling hand clutched his sleeve tighter, his yellow eyes blown wide even through the haze of blood. His voice cracked, panicked. "Your sword’s gone. You can’t—"

"I know." The words snapped sharp, flat, clipped—merciless as steel.

His sword was gone, but his blood was not. He could still fight barehanded, his body a weapon. But without obsidian steel to focus his strikes, his control would falter. Against a regenerating S-Class... that margin mattered.

The tentacle arced downward. Closer. Seconds from crushing Mel into the stone.

The weight pressed sharp against Kairo’s chest—not fear, not hesitation, but the razor edge of urgency. Panic licked at his ribs, but he forced it back, chained it under cold resolve.

His jaw set, eyes hard. He knew what to do.

But for a heartbeat, just one heartbeat—he hesitated.

And that was the mistake.

The cavern split with twin screams.

"Mel!" Zaira’s voice cracked, torn raw with terror.

"Mel! No! Give him back, you motherfucking—!" Mio’s scream overlapped hers, his silver threads snapping wild in a storm of fury.

But it was too late.

The tentacle didn’t crush Mel.

It wrapped around him. Twisting. Binding. And then, with one grotesque pull, it yanked his limp body skyward.

"No—!" Eli’s voice broke into a desperate rasp, his chest heaving, his bloodied lips trembling. "Kairo, please... please just use my blood. We don’t... we don’t know when—"

The monster shrieked.

A piercing, bone-splitting cry that shook the cavern as it retracted its limbs. One of them curled tight around Mel’s body, dragging him higher, deeper into the ceiling’s black mass.

For a moment, silence pressed heavier than the monster’s shriek.

No one moved.

Zaira’s breath tore ragged in the air, her dagger trembling at her side as her blue eyes blew wide. "Captain—! We have to do something! It’s taking him—!"

Mio’s voice cracked raw, wild with panic. "Don’t just stand there! Tell us what to do!" His threads lashed uselessly against stone, every movement more desperate than the last. "It’s eating him alive!"

Kairo’s gaze stayed fixed on the ceiling. On the tentacle coiling tighter, dragging Mel higher. The translucent flesh rippled, grotesque and deliberate, as if the monster were drinking him into its body.

For the first time in years, frustration burned in Kairo’s chest so sharp it made his teeth grind. His black eyes narrowed, his jaw tight as iron—but the faint tremor at the edge of his breath betrayed it.

’It’s absorbing him. Like it swallowed my sword. No... it’s worse.’

The taste of iron filled his mouth before he realized he was biting his own lip, sharp enough to draw blood.

He never bit his lip.

Never.

Below, Eli moved. His blood-streaked face tilted toward him, yellow eyes glowing faint through the haze, desperate.

His trembling hands lifted, wrists bared, raw grooves from Mio’s threads still seeping sluggish crimson.

"Use it." His voice was torn, weak, but clear. His chest heaved, every syllable a knife. "Kairo—please. Use me. Before it’s too late."

He kept looking between Kairo and the monster, like he was begging Kairo to choose. Begging him not to waste another second.

The cavern shook again. The tentacle pulsed, translucent flesh rippling as Mel’s limp form sank deeper, his outline already warping, merging with the monster’s grotesque mass.

Zaira shouted again, voice breaking. "Captain, he’s slipping—!"

Mio’s scream cracked raw. "What do we do, Captain!"

And Kairo—

Kairo’s chest clenched, fury and calculation colliding so violently it made his breath stutter.

For the first time since stepping into this dungeon, he felt the burn of helplessness clawing at his composure.

"Fuck." The curse tore out of him, sharper than steel, uncharacteristic in its weight. His voice cut through the chaos like a wound splitting open.

He turned. His grip tightened around Eli, then shifted—his free hand snapping forward, seizing Eli’s trembling wrist.

The boy gasped, his yellow eyes flaring wide as Kairo raised the bloodied arm between them.

Kairo’s voice was low, clipped, every word deliberate, edged with the frustration boiling under his calm.

"...I will only use what was left behind."