The Demon Monarch System

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Unlike the rest of his demons, Ouroboros didn't actively train to grow stronger. There was no need to, because Ouroboros's rare bloodline carried out all the strengthening that he needed. The only thing Ouroboros needed to do was fuel his bloodline's power by devouring and falling into a dormant state that allowed its increased activity.

Therefore, by just devouring and sleeping afterward, Ouroboros grew stronger at a rate that matched or even eclipsed his peers―which were Apollo's strengthened demons. 

Additionally, growing stronger meant that the byproduct of his absorption―the Fragments of Sin―grew both stronger and purer. As long as he experienced a sizable jump in power, it wasn't far-fetched to say that Ouroboros could produce the next level of Sin Materia.

Hence, the reason Azridan once revealed that this serpent before Apollo was an indispensable item to any upcoming Monarch. Ouroboros's rare bloodline abilities enabled him to produce invaluable condensations of easily absorbed Sin.

'This little guy is truly more frightening than I expected,' Apollo said to himself.

Before beginning the evolution, Apollo checked Ouroboros' information just to understand what would change after he evolved from this lesser state.

「Name: Ouroboros [Companion]

Race: Lesser Demon (74.94%)

Title: N/A

Bloodline: *Silver Umbra Serpent (Undefined)

Demonic Anima Reserves: 1,000,000 units

Sin Volume: 15,000 units

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Strength: 1,000.0

Agility: 1,000.0

Intelligence: 1,000.0

Vitality: 1,000.0

Perception: 1,000.0

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Gula: Primary [Endless Devouring]

Avaritia: Primary [Unfading Appetite]  」

Since he was a Lesser Demon, Ouroboros's battle stats weren't overwhelming. However, Apollo immediately took notice of his absurd Sin Volume and Anima reserves. As a Lesser Demon, his reserves were ten times that of his household brethren!

Its Sin Volume was even twice that of Typhir, who was arguably the strongest demon in Apollo's possession, excluding Fuhrer. These numbers were simply absurd. However, when Apollo noticed the anomaly in Ouroboros's stats, he pondered just what it could mean.

'Ouroboros's current form is unsuited for combat since it lacks basic combat techniques,' Apollo muttered to himself. Thinking back to the times he depleted all of his Sin Energy and almost lost himself, Ouroboros merely served as a battery to recharge the exhausted Sin.

And, when they fused to fight against Valac, Apollo was filled with boundless energy. Although his strength didn't experience any shocking increase, his ability to sustain battle did.

Fortunately, Valac didn't outclass him by much. Plus, he was the holder of the Aura of Domination, so it leveled the playing field even more. 

'For now, the only role Ouroboros plays is that of our supplier,' Apollo thought while my moving his finger away from Ouroboros's scale. A moment later, he pointed forward, "Take on your true form Boros."

"Yessss!" Ouroboros exclaimed happily.

He slithered off of Apollo's shoulder and flew a distance of roughly 10 meters. During his flight, from his tiny state of approximately 30 centimeters, Ouroboros grew to over 3 meters long, adopting his genuine appearance.

Once that happened, Apollo smiled. 'He's truly growing well. It must be lovely to possess a bloodline like that.'

Not too long after, the same message appeared before Apollo's eyes. However, there was an overwhelming number of notifications that appeared because of Apollo's current actions.

〈System: You're choosing to assist in the evolution of a Soulbound Companion. There may be additional effects and costs to complete this process.〉

〈System: Your companion is of an extremely rare bloodline! The awakening of this bloodline will require more than the current experience.〉

〈System: Are you willing to convert your Sin Volume and Demonic Anima Reserves into Experience? [Y/N]?〉

Gradually, Apollo's expression filled with surprise. Admittedly, Ouroboros's evolution differed greatly from the rest. Whereas the system randomly generated the most fitting bloodlines for the others, Ouroboros already possessed a dormant bloodline.

However, awakening said bloodline seemed to be extremely difficult, requiring a generous amount of resources to sustain. In fact, Apollo was thoroughly appalled when he read how much more resources his evolution needed.

[Additional Sin Volume Required: 15,000]

[Additional Demonic Reserves: 150,000]

While Demonic Anima Reserves were only 75% of Apollo's capacity, the Sin Volume was another story. Because the system had yet to generate the exact number of his Sin Volume, seeing as he possessed 7 purified Vessels, the numbers made Apollo skeptical.

'How much of my capacity do these numbers cover?'

Though skeptical at first, when he recalled the fact that Typhir possessed 7,500 units, Apollo relinquished his apprehension. Because, as the ruler, how could his parameters pale in comparison to his subordinates?

Hence, Apollo chose to accept the price.

Almost 90% of all of his reserves were exhausted. However, Apollo realized that only 3 of his Sin Vessels were addressed in this absorption. 'Oh? That's promising. Let's see where things go from here.'

After accepting, the general message related to evolution appeared before Apollo. However, there were some slight changes.

〈System: The chosen companion possesses the potential to evolve. [Current Evolution:~75%].〉

〈System: Sacrificing 500,000 Experience is needed to raise the follower's evolution 1%.〉

〈System: Every 1,000 Sin Volume is equal to 600,000 Experience & every 10,000 units of Demonic Anima is equal to 50,000 Experience.〉

〈System: Do you wish to precipitate your follower's evolution? [Y/N]?〉

Apollo's eyes widened in shock as he read the disparity between the two resource conversion rates. Sin Volume was countless times more valuable than Anima, roughly 120 times greater.

This gave Apollo a general understanding as to why demons who operated on Anima alone, such gargoyles and other similar demons, were so much weaker and basically inconsequential. Their root power source was simply beyond compare!

After all, it was the ability to use Sin that gained the demons their position as an upper race, not the Anima.

Nevertheless, Apollo instantly agreed to allow the system to sacrifice over 12.5 million experience worth of resources to facilitate Ouroboros change.

Within the next instant of allowing the system to do so, Fuhrer's pupils contracted! "Move back now!"

Rmmmmmbbbbbllleeeeeee!

The entire cavern started to rumble as Fuhrer stabbed Brynhildr into the ground, generating an extremely thick Wrath Blanket. However, when he noticed Apollo outside of the barrier, his eyes narrowed.

"Young Lord! Come inside. Ouroboros's change will be dangerous," Fuhrer warned, splitting a small opening inside the barrier of Sin.

However, Apollo simply raised his hand and swiped it while shaking his head. The opening closed, which shocked Fuhrer. 'When did his control become this seamless? He can affect my barrier from that distance?'

"No need," Apollo said in an indifferent tone as he watched a pitch-black aura pulsate from Ouroboros's body. It was extremely violent, lashing about and destroying everything within a 50-meter radius, all except for Apollo.

A small orb encased Apollo, which this the black aura couldn't breach no matter how much it bombarded it. 

Furthermore, destruction wasn't the accurate word to describe the scene. After all, the aura wasn't destroying anything; it was all being drawn to Ouroboros's body like a black hole.

Concurrently, Ouroboros's eyes flashed with several colors while his body trembled and thrash about uncontrollably.

Apollo could hear a bestial roar filled with pain as he stared at Ouroboros. Because of this roar, Apollo's earlier indifferent expression began softening as he relinquished the orb around his body and walked towards Ouroboros.

With the orb gone, the aura tried to assail his body once again, only to be deflected the moment it touched Apollo's body.

〈System: The Supreme Demon Body's «Complete Immunity» has resisted the incursion of a fused Sin.〉

'Fused?' Apollo internalized with an astonished look. At this level, fusing two sins should be impossible. Then it hit Apollo, 'Could this be the source of Ouroboros' immense pain? If so, allow me to help.'

Apollo raised his palm and placed it against the horn on Ouroboros's head. He introduced a calm stream of his aura into Ouroboros's body, which soon caused his thrashing to calm down. But, in return, the absorption process sped up ridiculously.

'So that's what it was. His body fused Gula and Avaritia of its own accord, but his body has yet to mature, so it was beginning to devour itself. An absurd power to possess, but dangerous without control,' Apollo thought.

Meanwhile, Apollo's large palm soon looked tiny as he watched Ouroboros grow at a shocking rate.

5 meters…

10 meters…

25 meters…

Eventually, Ouroboros's body coiled around itself as he reached a shocking length of 50 meters! More importantly, two additional heads of identical size sprout from the base of his neck, resulting in a message.

〈System: Your Soulbound Companion has evolved.〉

〈System: Their dormant bloodline of the «Immortal Sin Hydra» has awakened.〉