Prologue: The Underworld War

The smell of blood, iron, rotten corpse, and burning field engulfed one of the most luscious plains in the underworld known for its beautiful landscape and view, but it now stood nothing from its former glory.

Hundreds of thousands soiled the plains as they stomped onto the ground with their armor all covered in blood from the carnage they fought.

In front of a defensive position was Klaus Crimson, one of the trusted aid by the underworld king, Lucifer, he was a loyal knight who fought alongside his king since they defeated another former underworld king, Hades.

Behind Klaus were more than 700,000 thousand soldiers and knights who were led by powerful individuals known as the 7 Deadly Sins, despite being beside Lucifer since the start of his campaign, Klaus didn't qualify to be a Deadly Sin because he lack power.

Focusing his attention on the enemies, they were facing a much larger force, compromising of more than 1.5 million demons, Beelzebub was riding his armored hellhound, sporting a dark long sword and armor with similar designs, the Blood Horde, the name Beelzebub given to his army was slowly approaching the defenders.

Not long after, the two armies met each other, Beelzebub approached the defense lines of Lucifer's army and demanded surrender as he threatened death upon them.

As expected, Beelzebub's offer of mercy was rejected, and the battle was inevitable.

The Blood Horde charged as their powerful generals lead them, while the defending army was being led by the seven deadly sins.

The moment the enemy crossed blades with his line of defense, Klaus unleashed his prowess as he manifest various powerful spells killing hundreds and then thousands of enemies, yet, compared to the degree of power the enemy generals and the seven deadly sins field, it paled of what Klaus mustered all his strength.

Still, Klaus was not disheartened as he continue to fire a barrage of fire elemental spells which is his most compatible element. Regular demons and mains were helpless against the degree of power Klaus unleashed, as his flames burn their flesh and burn the soul itself giving his enemies absolute and certain death, completely disintegrating their bodies and existence.

And just like that, for the next 100 years, Klaus was fighting on the front lines non-stop, giving his best even in the bitter end...

...

Inside the large throne room, various bodies were severed, mangled, and incinerated indicating that there was a battle that ensued in the area not a long time ago, one of the bodies laying unconscious was Klaus, even a hundred years later, he still fought for his king, yet, his seemingly unstoppable might was stopped as Beelzebub himself punched Klaus in the gut as if swatting a fly, Klaus was out of commission instantly.

As his consciousness returned, Klaus slowly rose the rubles and piles of bodies, he slowly walked towards the main room, and with each step, Klaus felt as if his body was fielding the last of his life force, he knows death was imminent yet he still trot towards his king, as sight many powerful individuals would want, a loyal knight whom shall sacrifice himself for his master.

Klaus forced open the massive golden gate, this is the room where he always sees his king, sitting on the throne in his majestic regalia.

As the massive gate swung open, the former majestic room, filled with various beautiful designs, masterpieces, and relics, was reduced to a slaughterhouse as blood and remains of whatever unfortunate soul they were, filled the whole room.

The sight was gore, yet, Klaus was not bothered, he fought on the front where the lines themselves were considered a meat grinder because of the degree of death that occurred there.

What Klaus was bothered about, however, was his king, now lifeless laying on the bottom stair of his throne, sitting on the throne made of unknown metal was Beelzebub, who was not looking any better, his body was beaten up, full of various shallow and deep wounds, missing an eye and an arm, it was evident that Lucifer did not give him a good time.

Using his one eye, Beelzebub gaze at a familiar face, the person he saw in the front when he started the campaign who also killed a good chunk of his Blood Horde, and the brave person he punched in the main gates of Lucifer's castle.

He was loyal, brave, and fearless, yet, fate made fun of him by making him weak, so weak he only needed one punch to kill him, or so he thought.

"You are persistent for sure, Lucifer is lucky to have many followers like yourself, giving it all despite the odds. You. What is your name?"

Despite being devastated by the death of his King and his body which is nearing death, Klaus calmly gazes at the new king of the underworld, Beelzebub, and replies.

"I am Klaus Crimson."

"Klaus Crimson, one of the names I deem worthy to be remembered," Beelzebub said.

"I am humbled, my lord, I shall too, remember your name as if I'll ever forget the name of whom slaughtered the most powerful devil I'd ever know," Klaus said as he grins, he gave Beelzebub the respect he earned, it was no use in trash talking with the winner who played good and fair.

They were the losers, and the winners must take all, be it power, fame, or wealth. Unlike the other world's belief, demons and especially devils are not barbarians who engaged in lowly practices, only low-blood demons and mortal demons do it because they were desperate for power as their souls cannot achieve nor ever hold it.

However, it is undeniable how demons and devils can be chaotic, especially in war.

Releasing a tired and heavy sigh, Beelzebub straightened his back and spoke, "Normally I would kill you, Klaus, yet, the spirit you displayed this whole time was probably the most impressive among warriors who fought in this war, and it is undeserving for you to die so fast. Tell me, Klaus, what do you desire?"

A heavy question coming from a very powerful individual and an underworld king nonetheless. Klaus will inevitably be in deep thought, it was obvious that Beelzebub will grant whatever Klaus would wish.

Klaus contemplated his life since he was born as a low-born devil, he spend his time as a kid honing his magical skill, specifically his fire element to the point he can now burn the very soul of his enemies giving them true death.

After that, he was recruited by Lucifer's Grand Army, going campaign after campaign till the reign of his master was over.

Klaus did not experience the fabled 'normal life, as if you can get that here in the underworld which is full of violence and war.

He did not experience much in life other than war, he did not have the luxury the high devil born have where they go on trips to various places, parties, fun events, and getting lovers they spent with.

Klaus was a loner, it's not like he have no social life, he was only surrounded by demons who are all low borns and only knows to follow orders, eat, sleep, and repeat.

"I wish... For a normal life." Klaus unintentionally uttered.

Beelzebub raised his brows and then started laughing like a maniac, "Normal life in hell!? Hahahahahaha! Klaus, you're funny, I like you!"

Beelzebub laughs for good 30 minutes while leaving the awkwardly smiling Klaus listening to his laugh.

After finally settling his laughter, Beelzebub, smile genuinely, "While I can't give you a 'norm life' in hell, I can give you one in the other world, Klaus, however, you will be exiled here in the underworld and to never return! Now, you can take your retainers with you there and some servants if they are still alive! Hahahahaha! Now go! Before I change my mind! Hahahaha!"

Beelzebub then proceeded to heal Klaus from his grave wounds, Klaus was instantly healed and as if his body was reborn, truly the power of an underworld king was something, he was also given the seal of Beelzebub.

Klaus then finds his retainers and servants given to him by the late underworld king, Lucifer, he also brought his belongings in his special storage which is a devil-born ability.

He then traveled towards the World Gate Relic, and he was then transported by the gatekeepers to a random world, while his servants were sad about the fall of Lucifer, Klaus was having mixed feelings, he was broken that his master was defeated, yet, he also felt excited as he starts a new in a different world and lives a life of the fabled 'normal life'.

To himself, Klaus he will start only a normal life, however, the world where he will settle shall feel the change he will bring.

...

A/N: What do you think of the prologue?