Harem Startup : The Demon Billionaire is on Vacation

Chapter 78 – This Vacation is Out of Control

The Hell financial department’s office felt too quiet.

He sat behind the massive black-and-gold desk where his son usually worked — the desk that had once been his before Lux took it over for the last two centuries. The hell-forged obsidian surface gleamed under the flickering infernal lights, but it felt... different now.

Colder.

Bigger.

Almost intimidating.

Like the desk itself missed Lux.

Zavros took a long sip of his coffee, fingers tightening slightly around the elegant black mug as several holographic financial screens floated in front of him.

All of them filled with data.

A ridiculous, terrifying amount of data.

Revenue reports. Cross-realm trade agreements. Blacklisted soul bond indexes. Inflation control charts from lower sectors. And something called: ”Interdimensional Liquidity Streamlining Model 3.7”

He sighed heavily, rubbing his forehead.

”I’m back to this hell again...” Zavros muttered under his breath.

More screens popped open automatically, displaying stable infernal stock charts — stable, when two centuries ago the same charts used to pulse like seizure-inducing seizures.

Zavros blinked at one of them.

”Is that... positive growth?” he mumbled, eyes narrowing. ”Two hundred years and this kid tames the soul inflation rate?”

Another window updated automatically — reviewing newly sealed demonic contracts filed under Greed Department v3.9 — all filed with surgical precision, handled by systems that seemed to predict corruption attempts before they even started.

His eye twitched.

Seraphyne’s voice floated into the room like silk as she entered, hips swaying lazily, her gown slipping over her curves like liquid rose petals.

”You can’t let Lux handle everything forever, dear,” she said softly, her voice playful but carrying that mother edge. ”We’ve already abandoned him long enough.”

Zavros let out a long groan, gesturing wildly toward the endless screens around him.

”I know! I know we left him! I just... I didn’t expect this!”

He slammed his coffee cup back down onto the desk. ”He fixed everything!”

Seraphyne smiled sweetly, stepping closer behind him, resting a hand on his shoulder.

”Isn’t that a good thing?”

Zavros ran both hands through his hair like a man on the verge of nervous breakdown. ”It is! It absolutely is. But—”

He waved his hand toward one particularly horrifying system window titled.

[Greed Adaptive Contract Enforcement v4.2 — Powered by Autonomous Sin-Affinity Detection]

”—this is terrifying.”

Seraphyne leaned over slightly, eyes glancing across the data streams as the graphs scrolled rapidly.

”Hmm...” she hummed. ”He actually built predictive enforcement models?”

Zavros groaned again.

”And he automated multi-realm taxation without summoning a single debt hound. Do you know how long it took me to negotiate those tax terms between Purgatory and Infernal Sector Four?” He gestured helplessly. ”Lux did it in three clicks while sipping espresso!”

Seraphyne chuckled softly, voice warm. ”He always was smarter than both of us combined.” She winked. ”Got that from my side.”

Zavros shot her a look. ”Seraphyne.”

She batted her eyelashes innocently.

”But really,” he muttered, eyes drifting back to the display. ”He is restructuring the entire damn department like some infernal fintech startup... it’s kind of illegal.”

He rubbed his temples again.

”I mean I’m proud—don’t get me wrong—I’m very proud. But also...”

He trailed off, exhaling slowly.

”...a little terrified.”

Seraphyne grinned. ”That’s how you know he’s ours.”

Before Zavros could respond, another window suddenly popped open, accompanied by a sharp, flashing alert.

[WARNING: Unregistered Power Spike Detected]

[Source: Mortal Realm — Earth Sector]

[Severity: High]

[Timestamp: 00:03]

Zavros’s expression froze.

”That’s the third one today,” he said slowly.

Seraphyne’s eyes narrowed. ”Same location?”

”Yes.” Zavros’s voice was flat now.

Another spike flickered across the screen.

[Secondary Surge Detected: 00:04]

Zavros finally stood from the desk, his body tense. The data screens continued to flicker, but his focus had narrowed sharply.

”This... this isn’t normal.” His voice dropped into something darker now, the weight of centuries of experience heavy behind it.

Seraphyne’s smile faded as she caught the shift in his tone.

”What do you mean?”

Zavros exhaled slowly, eyes locked on the warning screens still pulsing with rising power surges.

”Something is happening in the mortal realm,” he said softly. ”Something big. An entity... is growing stronger. Rapidly.” His jaw clenched tighter. ”And whatever it is—it’s doing it without an affinity or level cap.”

Seraphyne’s eyes widened. ”No cap?” she repeated softly, like tasting the words. ”That’s not possible.”

Zavros shook his head. ”And yet... it’s happening.”

She stepped closer, voice dipping with concern now. ”Is it a demon?”

”I don’t know.”

”An angel?”

”I don’t know,” Zavros repeated, his voice flat. ”But it’s dangerous.”

A silence fell between them, thick with the weight of something unspoken. Then Seraphyne’s voice dropped even softer.

”What about Lux? He’s in the mortal realm too.”

That’s when Zavros finally faltered—just slightly.

His gaze flicked toward her for a second before returning to the glowing data streams.

”That’s exactly why I need to know,” he said.

”You think he’s under attack?” she whispered, now fully serious.

Zavros shook his head again, slower this time. ”I don’t know. But whatever’s happening down there—it’s big. And if our son is caught in it...”

His voice trailed off, his jaw flexing again.

Seraphyne was already moving, her fingers dancing through the air as she activated several more surveillance threads. ”Then let’s find out.”

Zavros snapped his fingers sharply, his voice dropping into full command.

”Open source window. Full trace. I want visual.”

The hellfire data core ignited, spinning like a crimson vortex as the system obeyed.

[Processing...]

[Locating...]

[Establishing Cross-Plane Link...]

The swirling infernal rings stabilized — and the image finally snapped into focus.

Both Zavros and Seraphyne froze.

Their son.

Completely naked.

His red eyes lazily half-lidded as he sat back against the headboard, casually sipping a glass of wine, completely relaxed like this was nothing more than an evening nap.

Next to him?

The Kraken girl tangled in sheets, still sleeping, her tentacles draped possessively across his body like oversized ribbons, her lips marked with faint bruises and messy lipstick.

The suite around them?

Wrecked. Completely.

Lux looked entirely unbothered. Relaxed. Almost too relaxed.

And still radiating unstable power from his latest pact.

Seraphyne blinked, her cheeks flushing ever so slightly.

”Oh my...” she whispered. ”Well... our boy’s certainly... blossomed.”

Zavros’s expression was more complicated.

Equal parts horror.

Equal parts reluctant pride.

He whispered under his breath.

”...My son’s a monster.”

Then paused.

”And also... a genius.”

Seraphyne sighed dramatically. ”Like mother, like son.”

Zavros rubbed his temples again, voice dry.

”...This vacation is out of control.”