After Ten Millennia in Hell

His eyes had rolled back, and he had slumped to the ground trembling. Saliva dripped from his mouth, and black blood poured out of his body.

"Phew." Oh Kang-Woo stretched out his arms, seemingly refreshed. "I feel a bit better now."

The irritation occupying his mind had somewhat disappeared.

[Th-The maximum value of n(B)...]

"What, you still haven't solved it?" Kang-Woo sneered.

He wasn't expecting to get an answer anyway.

The demons had lived a long time, but that didn't mean they were more knowledgeable than humans. Demons weren't interested in anything besides fighting after all. There were a few exceptions, but demons on average were very dumb.

'Well, actually…’

Kang-Woo also didn't know the answer to that question either. He'd searched for a math problem on his smartphone and had said it without thinking too much about it. He was an orphan, so academia was something he never really had the time for.

"Ah, that was very productive."

Kang-Woo smiled in satisfaction.

Things could have gotten very dangerous due to the irritation in his mind.

'That was dangerous.'

The irritation that Kang-Woo had felt couldn't be compared to human levels of irritation as he was a demon. A demon's body amplified the demon's desires and emotions. Demons could get into a fight to the death just because their shoulders happened to bump while they were walking past each other.

'It was really bad during my battle with Mammon.'

Back when Balrog had been driven to the brink of death, the intensity of Kang-Woo's feelings of irritation had been really high.

'Back then...'

He recalled a scene from the past. The ground had been destroyed, and the sky itself had been burning black. There…

"Tsk."

Kang-Woo clicked his tongue.

That scene wasn't something he wanted to remember.

"Let's see…"

Kang-Woo took out his smartphone, changed to selfie mode, and looked at his eyes. Behind his mask, his eyes had returned to his usual white sclerae and dark brown irises.

'They went back to normal.'

The color of his eyes changed whenever he got overly excited or enraged, so he had to be careful. Otherwise, something similar to what happened back then during the battle with Mammon could happen once more.

'Now that I think about it, that son of a bitch Satan was the same as me.'

Kang-Woo realized that, unexpectedly, he and Satan had many things in common.

He frowned and muttered, "To think that I have similarities with the Demon of Prophecy."

It wasn't welcome news. Someone could think that he was the Demon of Prophecy instead of Satan. That was something he couldn't accept.

'That aside…'

Kang-Woo turned and looked at Malphas, who was endlessly mumbling something while trembling. It was as if he'd completely lost his mind.

"I think he's too far gone to interrogate," Kang-Woo said, belatedly regretting having gone too far.

He then turned from Malphas to Halphas. Halphas was lying on the floor, unconscious.

Kang-Woo walked toward him.

"Sir, you can’t sleep here."

He nudged Halphas with the tip of his shoes, and Halphas slowly opened his eyes.

[Kuh! Urghh!]

Upon waking up, Halphas groaned in pain and grabbed his wound. He raised his head. His eyes were full of fear while looking at Kang-Woo.

[Y-You...]

Bash!

Kang-Woo stomped on Halphas' face, embedding his head in the ground.

Kang-Woo spoke quietly, "I'm sure you know you're in no position to ask questions, don't you?"

There was silence. Fortunately for Halphas, he wasn't dumb enough not to realize the situation he was in.

Kang-Woo looked down at Halphas.

"Who are you three?"

He had never seen them before. Their strength was comparable to the higher-ranked demons of the Ninth Hell. Yet, he'd never seen them during all the years that he'd waged wars in the Ninth Hell.

'Well, I guess it's possible that I just overlooked them.'

Just because he was the Lord of the Nine Hells didn't mean he knew every single demon there. The Nine Hells were massive, and an enormous number of demons lived there.

However, there was another problem…

'They used Lucifer's power.'

The black sphere with powerful absorptive capabilities was a technique that Lucifer had used in the past when he fought against Kang-Woo. The characteristics of the technique were too similar to call it a coincidence.

"Are you Lucifer's retainers?"

[Kuh.] Halphas frowned.

That short reaction was enough of an answer.

'I don't recall seeing these guys among Lucifer's retainers.'

Kang-Woo thought of Halphas', Malphas', and Phenex's faces. They looked identical.

They had such a unique appearance as a trio of identical demons, so there was no way Kang-Woo wouldn't be able to remember them if he'd seen them before. After all, the war against Lucifer had lasted for a very long time.

'Are they new retainers?'

There was a high chance that was the case. Kang-Woo stroked his chin and fell into thought. If they were newly made retainers, things would get troublesome.

'Has Lucifer recovered his old level of strength already?'

These three demons were not weak in the slightest. Kang-Woo had only been able to overwhelm them because he'd recently absorbed Tirion's power and obtained massive growth. If he wasn't able to use demonic energy from the deep end of the Demonic Sea, he wouldn't have been able to overwhelm them so easily.

'He probably didn't raise these retainers in the Ninth Hell.'

The place that Lucifer had fallen into was the continent of Aernor. Kang-Woo wasn't sure what kind of place Aernor was, but it probably wasn't brimming with demonic energy like the Nine Hells. So, if Lucifer had been able to create demons that were this strong despite that, it just showed how powerful he was.

'This isn't good.'

There was no way Lucifer would have only made three retainers. Kang-Woo wasn't sure how many more retainers Lucifer had made and how much stronger they would be compared to these three.

'I heard he battled angels.'

Then there was a chance Lucifer had made more retainers so that he could fight angels.

"Damn."

Kang-Woo frowned.

So many beings had crossed from the continent of Aernor to Earth. It showed that the dimensional wall separating the two worlds had become very weak.

He was already getting irritated while dealing with the Demon Cult. If Lucifer's forces started to cross to Earth more frequently, then it would be an absolute hassle.

'Just leave me the fuck alone, you sons of bitches.'

Kang-Woo just wanted to enjoy life after the ten millennia of suffering he'd gone through, so why was everyone trying to bother him?

'Fuck. What did I do to deserve this?'

He could confidently say that he'd lived an honest and good life. It just wasn't fair.

Kang-Woo sighed and asked, "So, why did you guys come here?"

[I-I cannot s—]

"Do you want to become like him too?"

Halphas looked at Malphas, who had gone insane from the extreme amount of pain he'd experienced.

The fact they were demons didn't mean they didn't feel anything after seeing something like that. No, demons would probably be even more fearful since they were obsessed with the desire to live as long as possible.

[W-We have come here to find Satan.]

"What?"

Kang-Woo looked at him in surprise.

'Satan is truly here?'

He felt as if he'd been hit in the back of the head.

"You came here to find Satan?"

[Yes. Recently, Tirion, the God of Heroes, was annihilated at the hands of Satan in this world. Lord Lucifer had commanded us to find him and request his cooperation.]

"Ohhh."

Kang-Woo nodded. He now understood what was going on.

'So, they were talking about me.'

For a moment, he thought that the real Satan had appeared on Earth.

'Wait, no.'

He shook his head.

'Satan is on Earth.'

It had been proven many times that Satan, the Demon of Prophecy, had come to Earth and was currently leading the Demon Cult. Kang-Woo had known for a while that Satan was indeed on Earth.

'Yes, of course. Satan is the one who killed Protector Alec and Tirion's apostle, Reynald.'

He'd almost forgotten about something very important.

'That aside…'

Kang-Woo narrowed his eyes. 'Satan,' 'Lucifer,' and 'alliance'—those three words started to swirl around inside his mind.

"How much do you know about Satan?"

[Not much in detail. We just know he's been amassing power by creating retainers in this world and that he's currently battling the retainers of Gaia.]

'Oh?'

Kang-Woo's eyes brightened, and the tips of his mouth curved up.

'This…'

He could use this. The gears in his mind turned quickly.

Kang-Woo grabbed his stomach and roared with laughter, "HAHAHAHAHAHAHA!"

[Kuh!! Wh-What the—!]

Kang-Woo sent his demonic energy bursting forward. He deliberately didn't use his Trait, the Ruler of Demonic Energy.

Halphas' face became pale after feeling the colossal amount of demonic energy from Kang-Woo.

"'Not much in detail,' you say? You know nothing at all!"

[...What are you talking about?]

Kang-Woo snickered and continued, "You say you came here to find Satan when he's in front of your very eyes. How funny is that?"

[Wh-What?!]

Halphas' eyes widened as he thought, 'This man is Satan?'

There was no way. The man standing before Halphas was wearing a mask, but he was clearly a human. Leaving his appearance aside, why would Satan be protecting a retainer of Gaia and attacking them?

"Seeing your reaction, it seems like your eyes are for decoration. I will take this opportunity to get rid of those useless eyes of yours."

[Wha—AARRGGHH!!]

Kang-Woo pierced one of Halphas' eyes with his finger, and a blood-curdling scream emerged from Halphas' mouth.

Halphas looked up at Kang-Woo while blood poured out of his eye. At that moment, he felt that the human in front of him was more like a demon than any other demon he'd seen before.

[A-Are you… t-truly Satan?]

"Can you still not see? Well... it seems like your other eye is useless, too."

[N-No!] Halphas quickly answered.

He bit his lip and nodded.

'This man is Satan.'

The man's chilling amount of demonic energy, his crazed actions, and...

'His eyes.'

The way his sclerae had turned black when he was enraged—it was a characteristic only very few demons had. If that couldn't prove he was Satan, nothing else could.

'What have I done?!'

They had been unable to recognize a prince of Hell and had antagonized him!

Halphas was so baffled that he couldn't even laugh.

[L-Lord Satan.]

"We finally seem to be on the same page. So, Lucifer requested my cooperation?"

[Th-That is correct.]

“Cooperation for what?"

[He said that you would understand if we told you that we should get hold of the Demonic Sea.]

"..."

It wasn't hard for Kang-Woo to deduce what Lucifer meant by getting hold of the Demonic Sea.

'Son of a bitch… He's after me?' Kang-Woo realized.

To be more precise, they were after the boundless sea of demonic energy, the Ten Thousand Demon Core, that he possessed.

Kang-Woo couldn't help but laugh. The dogs that had already lost once hadn't learned their lesson yet.

He laughed loudly again, "HAHAHAHAHAHA! How interesting!"

'You haven't gotten enough of a beating, Lucifer?'

The situation was different from the incidents involving Kim Jae-Hyun and Baek Kang-Hyun. Lucifer knew very well what kind of being Kang-Woo was. Yet, he was still planning to face Kang-Woo. That in itself was comedy.

'You already know who I am.'

Back when Kang-Woo had declared war on the seven princes of Hell, he had still been weak. He had faced dozens of losses, but he had ended up coming out victorious in the very end.

It hadn't simply been because he had become strong enough to defeat the princes of Hell. If all he had been was strong, then defeating them would have remained an unachievable feat.

"Tell Lucifer this," Kang-Woo said while grabbing Halphas’s neck. "I have already acquired the Demonic Sea."

[Wh-What does that…?]

"Hahahaha! Lucifer, you idiot! You truly know nothing!!" Kang-Woo grinned. "Why do you think I created the Demon Cult? The Demonic Sea is already in my hands! It's only a matter of time before I absorb its power!"

[...]

He looked at Halphas with eyes full of madness.

"Lucifer is in Aernor… correct?"

[Y-Yes.]

"Good. I was starting to get bored of this world."

Kang-Woo threw Halphas to the ground.

"Tell Lucifer this too." Kang-Woo's lips twisted into a smirk. "I will go there myself with my retainers, the Demon Cult."

[L-Lord Satan! D-Don't tell me…!]

"Hahahaha! Listen carefully, retainer of Lucifer."

Speaking in a voice filled with madness, he spread demonic energy to his surroundings.

"I, Satan, declare war on Lucifer."

Kang-Woo burst into laughter.

'Fight among yourseeeeeelves!'