A Demon is only as strong as its vessel. Theo did not want to become a Vessel for a Demon, and he also wanted to punish the asshole that tormented him for nine years.

He couldn't remember a majority of his life, but the torture remained, 'Oh, it was horrible.'

So, as revenge, the touted Archduke the frailest vessel he could find, a Woodland Floof.

Scattered across the entire multiverse, they thrive anywhere; adapting to their environments, they survive almost any harsh environment. Some of them mutate to variants that become impossibly hard to deal with.

Theo once encountered a Floof that made a fallen Dragon's Heart its home. It mutated to be strong enough to face Dragonkins. There was also a time that a Floof ingested the Fruit of Knowledge and became the most intelligent creature alive —for at least three hours until a poacher accidentally killed it—Floofs were versatile.

Theo had seen almost every single variant of them, so he knows all too well that the Woodland Floof was the weakest of the race. A creature at the bottom of the food chain, known to be an endangered species in most regions, is often beaten by rabbits and, in rare cases, hamsters.

'Now that I think about it, if I used the fox instead of a Floof, then the Demon would've just died… is this the Uneven Luck taking effect?'

[It is.]

'Legit? This is a better ability than expected. Take an L to get a bigger W… is this why those assholes can rise to be so strong after getting pierced in the heart? Damn~ this really is a hax. You Gods allow Heroes to possess these bullshit?'

[It is the desire of existence; it is not up to us whether they are born under the Star of a Hero.]

'That so? It's good to know Gods gets kick on the balls as well.' He was genuinely happy at this knowledge.

Fate, on the other hand, was not exactly enthralled — this gave Theo further satisfaction.

"Older Brother, are you all right?" From the side, Titus exclaimed as he approached with caution.

Theo looked at him and shrugged his shoulders, "Never been better—arhgh, SHIT!"

Theo yelped as a little one-eyed demon took the opportunity to snack at him.

"Older brother!" Titus went to his rescue and kicked the little Demon away. With a burst of his emotions came out his Hellfire he used to incinerate the little critters crawling out of the glowing rift on the ground.

"Shit! I forgot to seal the rift." Theo shouted as he held onto his bleeding leg, 'Dammit, every single time I do this, I always forget to close the Rift!.'

Only he could know how much he died because a random Demon came out of a Rift he opened and devoured him. Even if he wanted to fix the habit, Theo inherited this trait at least a hundred times.

Most Villains lack the ability and common sense to be thorough, and he just so happened to receive such traits over and over again, 'I can't bring my powers here, but their stupidity is programmed in my soul? What is this stupidity?'

"Older brother, are you all right!?" Titus anxiously asked.

"I'm bleeding, Titus, and I have no magia. What do you think?" Theo answered.

"Um—"

"I'm not okay, Titus—but thank you for caring!" Theo said through gritted teeth, and with a sharp breath, he could see that more miasma was slipping out of his idiocy, "Come on, help me up—aaaaahhhh, there we go."

"Wha-what's happening, Older Brother?" Titus was rattled as he asked, seeing demons escape their world.

Patting himself clean, Theo threw away the Floof Demon like a ragdoll and stretched his body, "Um, you know, nothing serious. Just a rift about to cause a massive flood of demons into the world and into our city."

"What!? Older Brother, this is not good. I thought we were stopping demons from getting into our world?"

"Oh, don't be so dramatic; we can still fix this."

"Really?"

"Yeah, just— hey, do you have anything sharp I can use? Mine got destroyed."

"Um, yeah, I have the knife crafted for us." Titus rummaged around his cloak and handed Theo a black knife.

'A Knife of the Night? Damn, he has taste.' Theo praised his Father, "Okay, stand back again—if you're squeamish, look away."

'Wait, he'd seen this before, right... you'll see more of this in the future, so best get used to it.' he was right, "You know what, best watch to get used to it."

Titus did what Theo said and watched in horror seeing his brother carve his own flesh. Titus wanted to call out, but Theo signaled at him to keep silent.

The mark was carved on his wrist, and then it glowed a purple light that accepted all the miasma the rift breathed out.

[Demonic Energy Detected — Corruption (10%)]

'Turn Demonic Energy into Magia…'

[Order Complete]

[Status: Magia Overflow

Magia Overflow: Your body has an inordinate amount of Pure Magia.

Do you wish to experience Body Purification? Y/N?

Body Purification: Purge internal impurities and strengthen the body from the inside out.]

"Lesson #2: Demonic and Divine Energy was cut from the same stone. They are thicker and stronger than normal sources and is bitch to get your hands on—" Theo walked over the

"But if you can get your hands on them, you can do almost everything with ease." Theo gathered the energy around the rift and controlled it to create a dome.

He had no magia, but he was an expert in controlling energy. Pure and untainted power like magia was easier than Divine Energy.

He flipped his hand and created the necessary dome to contain the escaping miasma; Theo dropped his blood on the rift.

"Lesson #3: If you want to close a rift, then use something that has Holy Attribute in them. Anything blessed by the Divine, the holier it is, the better, but a Saint's Blood is the best catalyst."

Theo clapped his hands together and then released a guttural soul to utter the word, "Silra!"

The dome of magia collapsed in and on itself and then forced the ground to close a little. Letting out an exasperated sigh, Theo had to repeat the process three times until his voice got raspy.

"Wooh, that was exhausting!"

"Did you close it, Older Brother?"

"Yeah, it wouldn't even look like we did a Fae calling here. Not a single demonic miasma remains as a true professional would do it." Theo bragged, "See for yourself."

Little by little, Titus approached, and when he stepped on where the rift was, he was astounded to see nothing remained but a little purple gash on the earth, "Older Brother, there's still a mark here, is that going to be okay?"

"Oh, that's the seal I used. If you're worried about breaking, don't worry, Silra may seem like a simple fix, but it can hold on for a long time. Even after a week from now, after the Rift has healed, it can remain. Though it would disappear as soon as the Rift closes." Theo explained.

"Older Brother knows Sealing Runes? I thought you didn't have mana? How can you do Arcane Arts?"

"That's not Arcane Arts, rather an Invocation."

"Invocation? Like in Spell Arts? But doesn't that also use mana?" Titus only grew confused at Theo's words.

"You're right, but also wrong. You see, before mana was a thing, pure energy was the only thing that others could use. So, the first Caster used Invocation to command the Magia using four words. These words also happen to be where all other Invocations were drawn from. They are called Four Words of Power."

"Then the one Older Brother just shouted earlier?"

"That's one of…." Theo paused as he looked around, "…hey, Titus, I don't train in any Arts, I can't jump up there, and I don't want to crawl back up."

"Ah, I have a rope; wait, I'll lower it from above." Titus left the cave through the hole above.

A vine was thrown down, and Theo began climbing after testing its integrity. Halfway through, however, he went back down and picked up the Floof and used his hood to carry it up.

While climbing up, he heard Titus continue his inquiries, "So, the one Older Brother used earlier? What was it? Silra, was it?"

"Silra? That one is used to Seal, and before you ask some more, I'll list out the others as well."

A weak laugh came from above.

Theo just shook his head, "Other than Silra, there is also Realis which is to Release; Qil, which is to attack; and lastly, Uruc used to defend. These are the most primal of invocations that even non-mages can use if they have enough magia, of course."

"Can I do it as well?"

"...I'll teach you after you get used to using Hellfire."

Theo finished the lecture as he exited the cave.

The first thing that welcomed him outside was Titus' puzzled expression, "How come I've never heard of this before?"

"Probably because they were lost in time. The Four Words of Power were once used a lot, but Sages found more convenient ways to invoke energy through mana, Wands, Magic Circles, and other ways after advancement. There's also the chance that using the Four Words of Power for too long can damage the throat and turn its users mute after prolonged use, thereby losing every quality of a Caster."

"Wait, if that's the case is Olde—"

"I'm fine~ I said, prolonged used not three shouts. It makes my voice raspy, but a night of sleep is going to fix that."

"I see, I see, I see… then what about the strange language Older Brother used to communicate with the Demon?"

"A forgotten language."

"The—"

"Stop, come on, that's enough question, let's go back."

The two walked away—Theo limped— from the scene of the summoning.

Titus offered to help him help but was refused.

"If you want to help me, carry this instead."

"The Floof? I thought Older Brother used it as sacrificed?" saying these words, though mundane to someone like Theo, felt a hint of guilt in Titus' heart. But, seeing it, breath tells him otherwise.

"I did use it as a sacrifice; that's the Demon you're holding."

"THE DEMON!?" Titus dropped the Archduke Demon, almost tossing it away.

Theo also told him otherwise.

***

"Okay, just make sure you don't talk about the summoning thing in the city so we can avoid our Family's eyes in the shadows, okay? If they ask about the ball-busting event, just tell them it was someone who called himself Heruzen."

"Yes, but, Older Brother, your promise, please keep it… and then please tell me more about the Four Words of Power."

"Yeah, yeah, I won't tell anyone about the I'trixian girl you fancy." Theo ignored the matter about the Four Word of Power.

"I don't fancy her! Anna's a… a friend… yeah, that's right… a friend." Titus saw Theo's questioning gaze and looked away, "Yes… just a friend."

"Stop acting like that; if you like someone, at least have the courage to admit it when you're not in front of them. How are you going to confess to her if you're already like this?"

"Confess!?"

"What? Please don't tell me the girl's engaged—I don't deal with engaged relationships." Theo began thinking, "Okay, but I might make an exception if the guy's a prick."

"… you've lost me, Older Brother."

"Oh, I'm thinking of setting you up with this girl."

Titus' face turned absolutely red as he shouted, "Wait, no, please don't do that!"

Theo laughed as he hurried back to the city.

"Older brother!? Wait! Please don't do anything unnecessary!"

Putting his younger brother on the verge of tears as they return from summoning a Demon, Theo was getting used to being a typical older brother.

Sigurd Manor

Using a secret path Titus dug East of the Ancient Library, they slipped out of the eyes from the shadow. The two brothers snuck back in without meeting any roadblock.

Behind the Ancient Library

"Give me the Floof Demon."

Handing the still Floof Demon over, Titus yawned.

"Go straight to sleep, Titus."

"Okay~what about you, Older Brother… aren't you going to sleep?"

"Not yet; I have something to take care of." Raising the Floof as he walked towards the nearest building he could find.

Theo walked away to finish his deal with the Demon, and Titus left to sleep.

The doors creaked open to the Ancient Library. The smell of old books putting a smile on Theo's face, "Oh yeah, this is a good place."

"Please tell me you're not here to destroy another of my haven."

"What the!!"

Theo jumped back and used the Floof Demon as a shield as a voice echoed from the side.

A middle-aged man playing strings looked at him with a sneer, "That Floof is not going protect you, Young.Master."

A cold tone came out of the watcher of the library, but the string wrapped around Theo's neck was colder, "…you sound a little pissed at me, Sir Karte."

"You destroyed one of my havens, and now you're back at another, hohoho. Young Master, I am not angry; I am livid." Karte saw Theo and the blood coming down, and with a sharp breath, he recalled his strings, "If you weren't the Leader's life, I would have loved to kill you."

Theo swallowed the lump on his throat. Feeling his throat as he exhaled, followed by a dry laugh, "If you want, you can sever my left arm, Sir Karte… though you'll have to clean the blood splatter."

"Don't even joke, Young Master. I'm already feeling tempted."

"Oh, I'm not joking. Though I will stitch it back up later."

Karte looked Theo in the eyes, and indifference was seen. It was the truth; he was not afraid of being hurt. Karte could see it, and he was at a loss for words. How was he supposed to react to such an offer?

"Tsk, forget it." Karte recalled his strings, "Having Alba infuriated isn't worth a library."

"Haha, seems like father saved me."

"I heard you ascended as a Saint?"

"I did."

"Then how come you're more irritating now compared to when you were a drunk?" Karte obviously did not appreciate Theo's answers, "So, what do you plan on destroying this time, and what's with that strange-looking Floof? You planning on adapting one when you can't even take care of yourself?"

"I do, and I plan on seeing any records of how to keep one." he nodded with a dry laugh.

"You do? Why do you reckon you'll find them here? It should be in the family Magister Libra…ry — tsk, that's right — Shit." He cursed underneath his breath.

"And that's why, it's under construction, so the best I have is to go through history books and see how they were tamed or rather, how other Beasts were tamed."

"Floofs are not known to be hostile, you know, maybe… just trust this one, you know."

Theo kept his smile as he slowly shook his head.

"Second floor, third shelf, second row. That's all you need to search through…."

"Thank you…"

Going up to the second floor, Theo was suddenly called to, "Young Master, wait!"

With a sharp breath, Theo turned to Karte with a smile, "I promise, I won't destroy anything." He was starting to get a little bit murdery.

"I know you won't because if you do, then I really will tear you asunder."

"Then what is it?"

"Your leg."

"My leg?" Theo looked down; his pants stained with blood were plain as day for everyone to see, "got bit by something."

"Are you okay? Why not go to the Medical Hall first?" Karte advised out of concern to Theo.

"I'm okay... don't worry, I won't leave blood tra-"

"I'm not worried about that...." Karte couldn't even finish his words out of embarrassment.

'Oh, he's that kind of person.' Theo shook his head in amazement, "...no, I'm all right. But, others might worry about me if they see the blood when I return, so, can I ask Sir Karte to get me a new set of clothes?"

"Okay then, I'll pick up some in your room."

"Yeah, su—Wait!"

"Is something the matter, Young Master?" Karte had to stop his exit as Theo called to him.

"Don't enter my room."

"Is there a reason why I can't go to your room, Young Master? Then where can I get them?"

"............................................!!!!!!!" Theo's head tilted, confused, 'Huh, why can't I let him in there? I don't have skeletons in my closet, and I don't have anything to hide yet... oh.'

She remembered something, and then he smiled in self-deprecation, "Rose is sleeping there; it's not proper for a man to enter without her consent."

Karte looked at Theo, and his callous expression softened until a wide grin replaced his frown, "I see, I see, I'll ask the maids for a pair then."

'I know that look... that's what I gave Titus earlier.'

He knows a teasing look when he sees it.

"Don't get the wrong idea, Sir Karte."

"Yes, yes, I understand, Young Master, I wouldn’t dream of it... I'm in the wrong, hahahaha!" Karte didn't even argue and left almost immediately.

[Pff~]

"Shut up, Fate… that’s enough of that, I have more important matters to take care of."

Tak!

"Ow you piece of—Mmmmm, mm."

The Demon opened its eyes, and the first thing it saw was Theo. It tried to rage, but its mouth was pinched shut.

It tried to fight back, but its attempts amounted to nothing more than a tickle, "Shut up, don't make any sound. Because of the nature of your summoning, that body has Divine Energy that equalizes your Demonic Energy. For the next 17 hours, you are vulnerable. Try anything, and I will snap your neck."

"Mmm, mmmm, m—"

"You know I don't understand hostage, right? I'll let go of your lips, cause a commotion or, I will kill you."

"Puaaah—you won't kill me…." The Demon said with a sneer, "You need me, so stop with your intimidation."

"First of all, stop being pretentious and just use the common language; I know you Demons speak every language. Second, what makes you think I need you? Start talking, else I will snap your neck, right here, right now."

The Demon saw Theo and began laughing, cackling, "You best stop the—wa-wa-wait, what are you doing?"

"What, I'm doing? Nothing, just going to snap your neck." Theo suddenly took the Demon by the head, "I told you, stop being pretentious, and you didn't answer my question either. I can see that you're going to drag this out, so I'll just kill you and sleep. Maybe that'll relieve some stress."

Holding the Demon close to him and gradually applying pressure, Theo's eyes never left the Demon's. Theo stared it in its soul, waiting for its eventual pop to echo and confirm its death… the Demon quivered.

"O-okay, I'll stop!"

"Too late, second chances are only given to those who deserve it." Theo rejected his pleas. He did not care what did was done; no more could be done.

Demons were known to be sadistic creatures. They torment others to get what they need and devour them when their desired emotion peaked. The Archduke was a similar existence, yet it kills with a purpose, to feed.

Theo… this human before him… wasn't doing anything to feed, 'He's doing this to eradicate my existence. To ensure that he would stop being a hind—'

"Just so you know, I'll eat you after this and then steal your abilities. Should've done that in the first place, right?"

'Oh shit, he's actually doing this to eat me!' The Demon panicked and quickly put its hands together; it began praying as it trembled in fear. It had no God, but it prayed to the creature in front of it, begging him, "Please… don't kill me… I can't die yet… I can't."

And then… as if it was a miracle, the pressure stopped.

The Demon saw Theo's eyes, and for a moment, there was a moment of hesitation, and then, he let him go.

Poof!

The Demon fell on the ground on its hind legs as it watched the human massage his temples. The human was in deep thought, thinking, trying to make sense of something.

He was in pain… a great deal of it. Distracted, disoriented, without anything to use as a defense, 'I can kill him.' The Demon thought to himself, looking at its stubby-clawed paws.

Jab him in the throat, let the blood flow and hide until he draws his last breath. But the Demon stayed its paws and decided to plop on its soft and bushy behind.

Its tiny body rested on the bookshelf, "Human, let's start over."

It chose to use its voice to wake up Theo.

"…" Theo did not immediately respond, but he managed to claw his way out of his mind. Theo looked at the purple Demonic Floof, resting its back on one of the bookshelves, looking all comical. He could not help but laugh as he joined it to his seat.

"You could've tried to kill me, Demon."

"I know… but you also spared me; why not tell me why you did that?"

"Meh, nothing really, you just looked pitiful."

"…maybe I really should've just killed you."

"Nah, you can't kill me. I would've snapped your spine before you cross my waist."

The Demon perched its lip; it knows Theo was not one to lie. The human had not lied once since their encounter.

"Wait, were you…." it was the only thing it could think of.

Theo smirked, "You're smart."

Only now did the Demon realize what was happening. The Human… it was playing him.

He should be angry, no, livid, but he just sat there and looked up to the circular window ceiling to laugh, "Gahahahaha, you are a bastard, Human… you win, I'll do what you want."

"Why are you acting like you don't have a choice in this? I want to cut you a deal. I want to do it through the Original Way… the Forgotten Ways."

The Archduke of Greed's eyes could not believe what it was saying. The Human actually proposed the Forgotten Ways, a method used by those who are equals.

"What are you planning?" there was no deal as good as this, and the Demon knew that.

"I am planning nothing, and I only want your abilities. Though I can get it if I eat your flesh, it will be weaker and cannot be enhanced, and I'd suffer the drawbacks, and I hate Demonic Power drawbacks for a Human. The proper method is cleaner and more beneficial."

The Greed Demon shouldn't believe him; it was not logical. Yet, he did not sense any malice from the Human. His words were genuine without any sense of false.

A Demon's instinct was sharper than any beast. It could detect emotions ten times more powerful than a Dragon smelling fear from a man that soiled himself. The Greed Demon's instinct was telling it to run away from the human, that he was dangerous, his self-preservation began to take over. His feet, however short, should have carried him far away by now, but something else was keeping him from escaping.

Something more extraordinary than a Demon's Instinct.

His purpose.

Greed.

Theo smelled dangerous, but the scent of opportunity was the strongest.

Beyond and King or an Emperor, the Human carried the smell of the brightest and most glorious future he could find.

Before, when his rage and the wall the Human kept to himself, he couldn't smell, but now, he could, and it was too enticing to reject.

The Greed Demon may have failed to perfectly read the situation earlier, but its instinct gave it a better gift. Its uncharacteristic selflessness not only allowed it to keep its life and another chance to speak with Theo and cut a deal.

"Even if it's the Forgotten Way… that doesn't mean I can get everything, can I?"

"You can ask for anything. Though if I reject it, know that it's because I can't do it, but because I disapprove of it."

"…what if I say I want to become the God of Demons?"

"I said anything." Theo only repeated his words.

'JACKPOT!' a door to an unattainable dream finally appeared for him to take, "You really are a Saint, Human!"

"You're pushing it, Demon."

Again, there was no lie, so he backed away with a swift apology.

Theo sighed at the excited expression the Floof Demon held.

"If that is all that you want then, I would like to make a deal using the traditional way." He explained with a yawn, "Let's do this; I want to turn in after this; I'm tired. I initiated the Deal, so you start."

With their backs against the bookshelves, the two raised their hands and stared at the circular window ceiling.

The both of them sighed; neither expected the situation to take this turn, especially the Demon.

Theo and the Demon had nothing noteworthy in common, but they both laughed at the ridiculousness of it all.

They watched the stars, sighed at the same time—

"I… want to become the True Dragon." The Demon gave its first demands.

"…accepted, in return make a Soul Pact with me, give me your abilities. Full control, without any of the drawbacks."

"Accepted, in return, it's not a one-sided deal; if I die, you die —if you die, I die."

"Accepted, in return, you can't harm anyone unless I tell you to."

"Accepted, in return, I want you to give me every Spiritual Being you kill as my meal."

"Accepted, in return, you can't tell anyone about our secrets unless I allow it."

"Accepted, in return, you won't try to kill me."

"Accepted, in return, you won't try to kill me as well."

"I have no more to say."

"I am the same; thus, with this, we follow the sealing of our words," Theo was just about to cut his skin when he saw a glowing golden ancient scroll appear in front of him, and so did the Demon. The scroll listed what they just said.

[Requirements Met: Devil's Contract has been activated]

"What's this?"

"A shortcut... I believe." Theo looked at the scroll and felt the information flowing in his mind, "Yeah, that's my Gift. Just agree if you wanna take the deal."

The Demon sighed, "We already listed the demands — I agree."

As they glowed with an ephemeral golden light, a Demon and a Saint entered an Oath that connects their lives for the first time in history.

[Soul Slot: 1/10

Archduke Demon Apophis]

"I can feel the connection already." Theo saw the Purple Mark of a Dragon eating its tail returned to his palm, but this time, it disappeared upon command, "Ahhh, feels nostalgic, somehow. How about you?"

"So, this is the connection of the Soul Pact… it feels surreal, as though my sensation is mired with another." The Demon looked at itself as it answered, "I know not why, but I feel the desire to cleanse myself of filth."

"Good, you can feel it too."

"You know why this is, Human? What is this power? Is it the ability to corrupt?" the Demon's eyes glowed with expectation. The power of corruption was rare to come by, even for him.

Stretching his body, Theo finally managed to exhale "I can't find the proper words to explain it, so let's just say I have a ton of issues."

And just those words alone made the Demon rethink its existence.

'…did I fuck up?'