Demonic Witches Harem: Having Descendants Make Me Overpowered!

Yesterday, Vulture informed Claude about a powerful monster guarding a cave filled with condensed mana crystals.

The creature—a serpent—had already reached the second stage of evolution despite being young.

Its strength came from absorbing the mana within the crystals, allowing it to grow far faster than others of its kind.

The serpent's body coiled, its massive length undulating with a grace that belied its size. Its golden eyes glowed like twin moons in the haze of the poisonous mist, slitted pupils narrowing at the sight of Claude's nonchalant stance.

"I will melt the flesh from your bones," the Serpent hissed, its voice reverberating through the cavern like thunder. "And wear your soul as a trophy."

Claude grinned, raising his black-flamed sword. "Big talk for a snake."

The Serpent didn't wait. With a screeching roar, it lunged, fangs bared, mouth wide enough to swallow a man whole.

Claude sidestepped in a blur, his boots skimming the rocky floor as the serpent crashed into the cave wall, shattering the stone with its mass.

Claude's blade slashed upward. A searing arc of black fire trailed behind it as he sliced across the serpent's neck.

Sparks flew, but instead of cutting clean through, his sword only carved a shallow gouge. Purple blood hissed as it hit the floor, but the beast barely flinched.

"Huh," Claude muttered, stepping back. "So your scales aren't just for show."

The serpent laughs, "You moron! How dumb of you to fight without knowing your enemy?!"

The serpent twisted midair, its body crashing down like a collapsing tower. Claude raised his hand, chanting under his breath. The shadows around him writhed, condensing into thick tendrils of dark energy.

"Shadow Entrapment"

The tendrils shot out, anchoring the serpent's upper body to the cavern wall. It thrashed, hissing in fury as it tried to tear free.

Claude used the opening to leap forward, blade slashing in a wide arc, aiming for the softer flesh beneath its jaw.

But the serpent spat a stream of venom straight at him.

Claude spun his sword in front of him and conjured a dark shield with his free hand. The black barrier shimmered and blocked the acidic spray.

The venom sizzled as it evaporated on contact, but the impact still sent Claude skidding back a few feet.

"I could've used that cloak," he muttered, flicking the acid off his glove.

The serpent shattered the binds with a scream, launching itself forward with terrifying speed. Claude barely dodged a strike from its tail, the force of the impact splitting a boulder in two behind him.

Claude's eyes narrowed. Enough playing around.

"Maleficarum Surge," he chanted.

Dark energy rippled from his body, forming a second set of phantom limbs—shadowy arms that floated behind him, mimicking his movements. With them, he could cast spells and fight at the same time.

"Hah! Stupid daemon, eat this!"

The serpent struck again, fangs glinting with toxin. Claude met it head-on, sword clashing against its upper jaw as one shadow arm fired a spear of darkness directly into its eye.

The beast shrieked, pulling back, one eye bursting in a flash of purple goo.

Claude didn't waste time. He chanted again, "Shadow Entrapment."

The shadows around him exploded outward in a shockwave, battering the serpent and pushing it against the cave wall.

He followed it, sword igniting hotter, flames pulsing with every heartbeat. He struck again and again, each slash carving deeper into its armored hide.

"AHHHH!!! YOU FILTHY WENCH!!!" It screams in frustration.

But the serpent was a beast of ancient origin, and it was not finished.

With a roar, it slammed its entire body into the cave floor, triggering a small quake. Stalactites broke loose and crashed around them as a geyser of venom erupted beneath Claude.

It burned through the stone, creating a pit of acid where he had stood moments before.

"Wow, careful, you don't want all the crystal mana to be a waste don't you?"

Claude leaped into the air, flipping midair as he conjured a pair of dark wings behind him, using them to glide past the serpent's head.

He spun and brought the sword down, stabbing directly into the wounded eye socket.

The beast thrashed violently, dislodging him and sending him flying into the wall. However, Claude's clone was faster as he chanted a spell, making tentacles holding his body so as not to hit the wall.

The serpent bled heavily now, but its rage gave it strength. "I'm not going to lose! I will not be lost!"

With renewed fury, it charged, mouth open, revealing rows of jagged, toxin-drenched fangs.

Claude lifted both arms, shadow, and fire converging into a massive orb of energy in front of him.

"Oblivion Nova."

The black sphere exploded forward, crashing into the serpent with blinding force. It pierced the creature's mouth and detonated inside, tearing through its skull from within.

The serpent convulsed, the entire cave shaking as its body slammed to the ground.

Claude stood panting, surrounded by smoke and darkness. The serpent lay still, half its face melted away by the final attack.

He wiped the sweat from his temple. "Shit... I killed it."

Claude covered his face with a sigh, frustration clear in his voice.

He hadn't meant to go that far. The plan was to tame the beast, not reduce it to a bloodied heap.

"I can't just revive it, can I?"

[Don't worry, Claude!]

[That cacodemon was merely a Serpentes Venom.]

[There are plenty more in this world. You can ask Vulture to find another—one even stronger!]

[That one couldn't even recognize you as the descendant of the Lord of Calamity! It didn't deserve to be your servant.]

Claude narrowed his eyes, noticing something off in Keira's tone. "You sound unusually cheerful."

[...]

[Would you rather I mock you or drown you in sarcasm?]

[Anyway, I'll extract its mana core.]

[And congratulations—you're now the rightful owner of this cave.]

[If you don't assign someone to guard it, another beast or cacodemon will claim it soon enough. The mana crystals inside can fill your mana pool, so it's not something you should leave unguarded.]

"Right... who should I entrust with something this important?" he murmured, rubbing his chin as he glanced around the cave.

The Serpentes Venom had vanished with its death, its venom leaving the earth slick and corrosive.

A few of the mana crystals had been tainted by the poison, but most remained intact—and the cave extended far deeper than he initially thought.

"I'll meditate here first and absorb as much mana as I can," he muttered. "Then I'll decide who's worthy of guarding this place."