System? And The Demon King

William stood in the middle of a vast forest. The trees towered above him, their branches intertwined and blocking out the sunlight. Shadows danced across the forest floor, and the sounds of unseen creatures echoed in the distance. William was alone—almost alone. His only companion was the strange system panel floating before his eyes, glowing faintly in the dim light.

[Host, I am the System and I will help you on your journey]

"What!? System!?"

[Host, you can ask me all the questions you want to know]

William didn't understand what this thing called the System was, but he realized that it was probably some kind of magic that had been given to him by the Being.

He decided to ask this strange thing called the System his first question.

"So, System, where am I now?"

[Loading... Complete! Host, you are now in the Great Forest]

Great Forest....

Great Forest was the largest forest on the continent of Aurilea. It was 10,000 square kilometers in area, and it shared borders with three countries. Sun Kingdom, Mung Dynasty, and Vangal. And these three are the largest countries in the south.

'Hmm.... That means I am far away from the Orinthia Empire. If I remember correctly, the distance from the Sun Kingdom to Orinthia alone is more than three thousand kilometers.

Then, William's thoughts were interrupted by the system ringing again.

[Host, do you want to see your status]

What is this?

Then another panel appeared in front of William.

Host Status Sheet

General Info:

Name: William

Title: Demon King (Level 1)

Race: Infernal

Alignment:Chaotic Ambition

Level: 1

HP: 100/100

MP: 50/50

Experience: 0/100 (to Level 2)

Subordinate: 0

Attributes:

Strength: 15

Vitality: 12

Intelligence: 10

Agility: 8

Luck: 5

Skills:—

Dark Aura (Passive): Radiates an intimidating presence. Weak enemies may flee; allies gain +5% morale.

Infernal Called (Active - 10 MP): Summon 1–3 Lesser Imps (Level 1) to fight for you. Duration: 5 minutes.

Demonic Infusion : increase physical attack 50%.

Soul Harvest (Unique Ability): Absorb fragments of souls from fallen foes. Grants +1% max HP/MP per kill (stacks up to 10 times).

★★★

Demon King!?

William was surprised to see this.

[Host, you are now a Demon. You will be given various missions and by completing them you will be able to increase your level.]

William then laughed like a madman. "Hahaha! So I am now a demon. No problem. I don't care about it now. I don't have any mercy for humans anymore anyway. So it's okay..... So I am now a Demon king Huh. ... I have to make myself stronger now."

Then William asked the system another question.

"How strong do I have to be to defeat the Orinthia Empire?"

"Host, if you want to defeat the Orinthia Empire, you have to pass at least 100 labels and have at least a few hundred subordinates under you."

William thought {That's right. The Orinthia Empire is one of the most powerful countries on the continent. If I want to get my revenge, I have to pass a very long road }

Then Suddenly a branch snapped behind him. William turned, his heart pounding as he watched the shadows between the trees. Something was moving —something big. A soft roar came through the air, sending a chill down his spine. It was the sound of a hunter, hungry and closing in.

Suddenly, the creature burst from the tree trunk. It was a wolf, but it wasn't any wolf William had ever seen. It had six legs, its fur was as black as obsidian, and its eyes glowed like molten lava. As William dove to the side, its jaws snapped inches from his throat, and he rolled behind a tree for cover.

William had no weapons, but he remembered his newfound demonic powers. He focused his energy and activated his Infernal Command skill.

[Infernal Called activated. Summoning Lesser Imps...]

A dark portal opened, and three small, grotesque imps emerged, cackling with glee. They immediately lunged at the wolf, clawing and biting at its flanks. The wolf howled in pain, its glowing eyes flickering as it struggled against the imps.

William seized the opportunity. He channeled his Dark Aura, amplifying the fear in the wolf's mind. The creature hesitated, its movements slowing as the imps continued their assault.

With a roar, William charged forward, his fists glowing with dark energy. He struck the wolf with all his might, the force of the blow sending it crashing into a tree. The wolf whimpered, its body twitching as it tried to rise.

[Target: Shadowfang (Level 2). Damage dealt: 30%. EXP earned: 10.]

The imps continued their relentless attack, and William delivered the final blow, his fist piercing through the wolf's chest. The creature let out a final, guttural cry before collapsing to the ground, its body dissolving into dark mist.

[Target eliminated. EXP earned: 40. Level Up: 1 → 2. Stat points allocated: Strength +2, Agility +1.]

William felt a surge of energy as his body grew stronger. His muscles tightened, his vision sharpened, and his reflexes quickened. He stared at his hands, flexing his fingers. They felt different—more powerful. The system's cold logic was clear: in this world, it was kill or be killed.

[New Skill Unlocked: Demon Summoning (Tier 1).]

William's screen flickered with options:

- Demonic Dog (50 EXP)

- Imp Soldier (200 EXP)

He hesitated for a moment. The Demonic Dog was cheap and expendable. It would have to do for now, he selected the option.

A pulse of dark energy erupted from the ground. The corpse of the Shadowfang dissolved into ash as a new creature materialized in its place. It was a hound, jet-black with serrated fangs and eyes that smoldered like coal. It growled low in its throat, waiting for William's command.

[Demonic Dog (Level 1) summoned. Bond established. Loyalty: 75%.]

"Scout ahead," William ordered. The dog obeyed immediately, padding silently into the undergrowth. William followed cautiously, his senses heightened. He didn't know what other dangers lurked in this jungle, but he was determined to survive.

William and his dog arrived at a place. It was a ruin. A statue of a horned warrior lay toppled, its face eroded.

[Quest: Investigate the Surrounding area.]

The holographic text shimmered at the edge of his vision. William knelt to examine a half-buried sword. The corroded blade showed traces of glyphwork beneath centuries of patina. Human craftsmanship, but the runes...

Before he could decide, voices echoed.

"Check the perimeter!" barked a voice like grinding flint. "Make sure no one else is around."

Four armored figures appeared - men clad in silver plate, with the symbol of sunlight etched on them.

'Are they from the Sun Kingdom?'

They were surprised to see William. Their leader, a woman with a scarred face, raised a crossbow.

"Identify yourself, stranger!"

[Targets: Mercenaries (Level 3-4). Threat Level: High.]

William weighed his options.

He was in a forest. A forest known to be the abode of monsters so no matter what he told them they would not believe him. So he had to fight them as a last resort. Since these people did not seem like good people either.

William decided to play it cool.

"Just passing through," he said, his voice calm but firm.

The knight's eyes narrowed. "Passing!? Is it written on our faces that we are stupid? We are in the middle of the Great Forest, home to terrifying monsters and tribes, and you are saying... Just passing by. You should have been given a better excuse. Imposter!"

I know it

The crossbow fired. William ducked behind a pillar, the bolt shattering stone where his head had been. His Demonic Dog lunged, tearing into a knight's thigh.

[Demonic Dog engaged. Loyalty: 85% (Battle boosts morale).]

William charged forward, his fists glowing with dark energy. He struck one knight in the chest, the force of the blow sending him flying into a tree. The knight's armor crumpled, and he fell to the ground, lifeless.

[Target eliminated. EXP earned: 40.]

William then killed another man by striking him in the shoulder and then twisting his neck. He was a Royal knight, so he was very skilled in fighting.

Demonic dog bites and tears apart a mercenary.

William delivered the final blow to the last mercenary, the scarred woman, his fist piercing through her chestplate.

[Targets eliminated. EXP earned: 120. Level Up: 2 → 3. Stat points allocated: Vitality +2, Perception +1.]

The last knight, the scarred woman, stumbled back. "M-monster…"

William aimed. "Yeah. I've heard that before."

[Disheartenment achieved. Bonus EXP: 20.]

He pulled the trigger.

As the Mercenaries' bodies cooled, William's screen updated:

[EXP: 175. Summoning options unlocked: Demon Swordsman (100 EXP), Imp Soldier (200 EXP).]

The Demonic Dog nuzzled his hand, its loyalty now 95%. William looked at the blood on his shoes.

[EXP: 175. New title unlocked: Slayer (Perception +1 vs holy enemies).]

William took a deep breath, his mind racing with the possibilities. He was no longer the man he once was. He was something more—something darker. And he was just getting started.

"Soul Harvest!" .