The Protagonist's Sister Is Actually The Strongest

“You probably don’t know how we met,” Fenrir said. “But the first time we met, both your brother and I were dying.”

“Wait, you were dying too?” Jack asked Fenrir in disbelief. “Weren’t you the boss of that Dungeon?”

“I wasn’t. Don’t you think it’s weird that Dungeon Gate’s still open after all this time since you left?!” Fenrir roared. “The boss of that place... is most likely the accursed bastard in charge of keeping me there until I died, as my powers were drained away by the Sealing Chains.”

“So there’s a whole dungeon as dangerous as that that hasn’t been cleared?!” I was just as surprised as my brother.

I don’t remember anything like this in the novel either! Was that Dungeon always ignored? If we could explore it and complete it, we could find even more clues about the Constellations and how Fenrir ended there to begin with, which was so overlooked in the novel. The author simply hated any kind of detail and always jumped into action right away.

“Anyways, this is not the time to talk about this,” Fenrir said, materializing at our side in the form of a giant black wolf made of shadows. “The reason why Jack is required to sacrifice memories is because of how weak I am.”

“It is because of you, and not me?” My brother was confused. “I thought I was the weaker between the two of us!”

“No, well, you’re pathetically weak without me.” Laughed Fenrir. “But that’s not what I meant. I mean it because most of the powers I lost. To restore them, I require a sacrifice of Causality. Memories gathered by someone powerful and seen by many Constellations, who are slowly building their own Epic, are like Fragments of precious Causality. When you sacrifice them, I can feed off that and regain my power, one bite at a time. Honestly, however… This will only lead you to lose most of your memories. Because I have yet to even recover twenty percent of them.”

“What? That’s…” Jack seemed dispirited, sitting over his bed. “Why did you never tell me that to begin with? Why did you keep it hidden? I thought that only after a few more”

“I… I’m sorry.” Fenrir sighed, throwing away his pride. “But I knew that if I had told you, it wasn’t as if you would have stopped. Before Anna woke up, you were a completely different person. Someone so dead set on doing his own thing that... I would feel bad if I ever considered getting in the way. Maybe I’ve gotten softer after fusing with your soul and sharing some of your emotions and memories as well. You’re like a dear brother to me now, Jack.”

“…” Jack remained in silence, expressionless as always. His blue eyes seemed to have regained a bit of their light as he smiled faintly. “You’re so corny.”

“H-Hey! I’m trying to open up here, and you mock me?!” Fenrir was incredibly embarrassed.

”So, in summary, our memories are Fragments of Causality?” I wondered. “That’s... I guess it makes sense. In a way, to grow stronger, we are required to develop an Epic, a Story. Constellations all feed off them. And Stories are made out of Causality above all else, right?”

“Y-You know a lot.” Fenrir muttered.

“Did someone tell you that too?” Jack raised an eyebrow.

“Ah… Yeah, there’s a weird monkey that’s always telling me stuff while trying to recruit me.” I sighed.

“That bastard of Sun Wu Kong is harassing you? He usually picks the most free-spirited assholes as Incarnations but chose you?! Wow… You’re really quite something to get his attention. He’s a high-tier bastard. Untouchable even when I was at full power.” Fenrir laughed.

[The Cosmic Throne {Monkey that Dances in Chaos} says that he had never told you any of such things to you!]

[He wonders how a mortal can be this shameless.]

Shush.

Wait, these guys are listening? I wonder if Fenrir hasn’t learned yet how to block their eyes. I suppose I could teach them while I’m at it.

“I’m a bit uncomfortable when there are too many eyes watching, though. They won’t let us alone even when we’re chilling inside our houses.” I sighed. “Let me teach you a few tricks.”

I taught them both how to block their watchful eyes using the same technique I had used before. It was easy, not because Fenrir had unlocked Cosmic Energy too, so my brother could wield it seamlessly. He wondered how I got such a technique, and I told him that Gaia taught it to me. Another lie for the pile of lies! I’m grateful my brother hasn’t gotten a lie-detection skill yet.

“This is incredible; they’re not watching us anymore!” My brother was amazed.

“The Cosmic Energy consumption is not good though, but I guess we can at least last for a couple of hours like this.” He sighed in relief. “Anna, thank you for teaching me this. Even as a Constellation, I was always rather, well, clueless about many things. Me and my siblings had to go through many trials, and we were fooled many times. I might have been the dumbest of the three, but I was also the bravest. But maybe recklessness can be mistaken for bravery sometimes.”

“Don’t sweat it, Mister Fluffy.” I patted his fluffy head. “Now, how can we fix this so you don’t eat my brother’s memories anymore?”

Unauthorized tale usage: if you spot this story on Amazon, report the violation.

“Y-You don’t have to put it that way.” Fenrir sighed.

He quickly sat down on the floor of my room, resting his head over his front limbs, as he started to think. He quickly brought up the dungeon we had talked about before.

“I never considered going back there because it was so dangerous. I was almost dead by then, all because of those accursed chains.” He sighed. “And the true boss of that dungeon has been mysteriously silent all this time, for years now. Jack told me no monsters have come out of that place yet. It is strangely eerie. As if... they’re waiting for me to return.”

“So if we go back there... Can we get some of your original powers back?” I wondered. “But how would that even work?”

“Well, to begin with,” Fenrir said. “Think of my original power as physical pieces of a puzzle. If I have them back, even if they are still sealed. I can simply use cosmic energy and other energies Jack will develop as he levels up through the System I made to unlock them one after another. Without needing Causality. However, when I lack these physical pieces of the puzzle, I must create them from nothing; therefore, I need Causality Fragments.”

“Got it.” I nodded. “So that’s how it works. How many of those Fragments of your Power are in that Dungeon?”

“Probably most of them; they were all being drained out of me in there. I managed to escape the commotion the monsters made and found Jack half-dead. I acted all high and mighty back then, but I was desperate. I needed some kind of vessel or host, or I would have fallen unconscious and might have never woken up ever again.” Fenrir confessed.

“Wait, seriously?” Jack was shocked. “And I was so scared back then! Well, you can also regain power by eating, right?”

“Yes, eating is part of the “energies” you accumulate. Technically, when you earn EXP, you’re stealing the Energies and a piece of the soul of the target.” He answered. “Therefore, that’s also delicious energy for me.”

“Interesting…” Jack was understanding his abilities much better now. “Though, you said not all your powers are there?”

“Yeah. I remember that. Uroboros took some. But there were others with him.” Fenrir recalled. “We did kill him and get half and half out of him. I won’t ask you to give it back or something; it must have been mixed up too much to fully recover anyway. But the others might still hold the Fragments. They were my Traits after all.”

“Who were they?” Jack asked with murderous intent. “Just say it.”

“Uroboros’ backer is not someone you want to mess with, Jack.” Sighed Fenrir. “But I do remember him and those helping him. They were the other Archdemons. But there’s someone else, the Archdemon King, the one known as The Devil. The True King of the First Hell. The {Chaotic King of Brutality} is one of his many titles. You may know him in your texts as Lucifer.”

“Lucifer, the angel that betrayed god,” Jack said silently, gripping his fists. “How... How strong is he?”

“Hahaha… On another whole level, He’s the King of all Demons, all of them. Across all Worldlines, he reigns supreme. He is so powerful that most Constellations speculate he’s already about to near the borders of the Realm Beyond and become Boundless, Ascending into a Void Ruler, unrestrained. If we ever get a chance to kill him, we have to catch him before he even becomes Boundless. But that… Even with everything we have, it feels more like a distant dream. Full of delusion. He probably holds my Fragments, or maybe he gave them to his lackeys, the other Archdemons. We’ve got six more to go.”

“Is Lucifer not an Archdemon?” Asked Jack.

“He’s the King; he’s not part of the seven thrones; he has a throne of his own.” Said Fenrir.

And I made him my enemy for killing his pet snake, yikes. Well, as strong as he is, just as Fenrir said, he’s greatly restrained. I have to take advantage of the time we’ll have. A few decades before he tries his Ascension to become Boundless. This “boundless” is merely speculative. In the novel, nobody ever reached that point.

But now that this world is no longer limited to the author’s imagination, anything can happen. Anything… And I have to be careful that things don’t become even more chaotic than they are now. But even then, it feels that such a wish is simply delusional.

[The {Seamless Abyss} is watching you in silence.]

Oh, right, you can see through the barrier. It must be because of the gauntlet; it does have your eye... Well, I don’t mind. I don’t know what your plans are. But you’ve helped me too much to think you’re an enemy.

[The {Seamless Abyss} squints its countless eyes. The endless abyss swirls silently around their boundless existence.]

[They glanced at you in silence. Nothing can be discerned out of their expression other than silence, boundless silence.]

I guess your silence is enough to soothe me a bit. If you’re truly someone I can trust, I hope you can prove it later. A few gifts won’t do it, alright?

[The {Seamless Abyss} shows no reaction.]

[Wait, no. There is a reaction.]

[Their endless abyssal shadows swirl to form something resembling a mouth.]

[They speak a single word.]

[“Gate”]

Gate… Wait, he spoke?! This is the first, even in the novel! He was such a mysterious guy. Yet he spoke to me?! What’s going on right now? Well, he said Gate.

Gate, like the dungeon, right?

[The {Seamless Abyss} is glaring at your brother.]

[And then at Fenrir.]

[And then back at you.]

[“Gate”]

Alright, I get it. So you want us to go there as soon as possible? I have a lot of things to do, though. But if you say so, I suppose it is an urgent matter. Alright, we’ll go. But this better be worth it! Will you gift me a few things?

[The {Seamless Abyss} squints their eyes.]

Are you angry? Okay, sorry! Your eye was enough. Sorry, I might have gotten a bit greedy there.

[The {Seamless Abyss} has gone to slumber within its endless bed of darkness.]

Goodnight, I guess.

[They have left something behind.]

Huh?

[It looks to be something physical. The item has been delivered to your inventory.]

I checked my inventory almost as if my life were on the line, finding inside something resembling a bottle full of black liquid. Is this… What is this?

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[The Seamless Abyss’ Miasma (??? Rank)]

An incredibly corrosive Miasma that is corroded by the endless appendages of a Void Ruler.

It is highly flammable, and once it touches something the Void Ruler deems unworthy, it will begin burning them and draining their energies rapidly, and it can break all seals.

It cannot be processed.

No more information can be discerned from the System’s current level.

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An item that can break seals and burn through “unworthy” things, huh? Just who’s the guy at Fenrir’s Dungeon that the Seamless Abyss hates so much?

Maybe we’re getting ourselves into something more dangerous than I imagined.

“Defeating such a foe as Lucifer... Well, nothing is impossible. It might take us an eternity, but we’ll eventually get there.” Jack smiled. “Anna? What’s wrong?”

“Huh? Ah…” I was feeling a bit dizzy as I stared at the item. ”Nothing, I just... I think we should go to that dungeon soon. Someone told me about it, a Constellation I can trust, and that has saved my life before. At least within a month, we have to get there and get back Fenrir’s fragments.”

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