Chapter 1

I had been betrayed.

In that very moment, as I came to this realization, a rush of blood surged to my head, causing an agonizing throb in my temples. Betrayed. Backstabbed by the very man to whom I had dedicated my heart and soul for so long. It had never occurred to me that I would become the protagonist of the 'loyal partner left in the lurch' narrative.

All the suffering I had endured, the sacrifices I had made to propel Fabian Corps into becoming the finest expedition team... In the end, this was my reward. Thanks to the quality of the information I provided and the talents I scouted for him, Fabian had managed to assemble a respectable expedition corps under his command. My support magic had greatly aided them, enabling Fabian and his expedition members to conquer dungeons and level up effortlessly.

When crisis struck, I had even sacrificed my left arm to save them all.

Initially, it didn't matter to me whether or not my efforts were acknowledged, as long as Fabian recognized what I had done for him. That was why I had endured being mocked by others, bearing nicknames like "Fabian's dog," and being labeled as a sycophantic support mage. I had endured it all for Fabian and him alone.

Yet, all I received in return for my dedication was abandonment, even though he knew I would die if he didn't come to my rescue. I knew I had to maintain a facade of composure, but suppressing my emotions was no easy task. What was worse, only Fabian and I were privy to my past devotion.

"So, have you made up your mind?"

A voice suddenly interrupted my thoughts, reminding me that we were not the only ones who knew.

I had been so preoccupied that, for a moment, I had forgotten about that man. That formidable presence, Mayer Knox—a beast, really—was also aware of what had transpired between me and Fabian.

Mayer Knox, the descendant of a hero, the only grand duke, the dark knight, the mightiest swordsman... He, the man with a myriad of titles adorning his name, was the one who exposed Fabian's betrayal and pushed me into a corner. Now, he persistently whispered sweet words of temptation into my ears.

He was also the one who had rescued me from the clutches of death, while Fabian had forsaken me.

"I shall ask you once more, Jun Karentia: will you join my expedition corps, the Dark Knights?" His low-pitched voice paralyzed me, echoing throughout our surroundings like the strike of a hammer on iron. Superficially, it seemed like he was offering me a choice, but in reality, he left me no option. The mere weight of that knowledge left my mouth parched.

I wanted to escape, but there was nowhere to run; I was within the Dark Knights' camp. Everything around me exuded the highest quality, from the tent material to the array of furniture, all befitting the title of grand duke. Yet, they all paled in comparison to the man himself, Mayer Knox. His black hair resembled a lion's mane, and his eyes, fixed unwaveringly on me, appeared as though they had been chiseled with a knife.

While Mayer was undoubtedly an impressively handsome man, his aura—his presence—made it impossible to casually appreciate his appearance. Clad in black armor, in perfect alignment with his reputation as a dark knight, he seemed as though he had been chiseled from solid black steel. In short, he was akin to a fortress, impervious to any words I might utter.

He truly was a formidable figure.

Having attained the title of grand duke at a young age, Mayer Knox had been the first and strongest swordsman to venture into the portal gates that emerged within the empire when the fellspawn's invasion began. Yet, at this moment, he appeared uncharacteristically anxious, a departure from his usual self. Was it because I was not responding to his proposal with an immediate nod?

"Why are you agonizing over it so much? It's not a bad option; in fact, it's the best one you have. I cannot, for the life of me, comprehend why you're rejecting it," he remarked, his tone urging me to accept his proposition.

And he was correct. After all, everyone aspired to join his renowned expedition corps, the Dark Knights. Moreover, whether it was before or after Fabian's rise to prominence, they had occupied the top spot in the rankings for an extended period. However, I was unwilling to accept his offer. This man... He was the core of the demon lord, the true final boss of the game into which I had unwittingly transmigrated.

The true final boss, the ultimate adversary—the most potent foe players would confront in the end, irrespective of their alignment as good or evil—the ultimate challenge.

***

The world I had unwittingly transmigrated into was an RPG game called 'The Sacred War.' Not only did the title evoke a sense of nostalgia, but the story also adhered to a very classical trope: defeating the demon lord who sought world domination. It was astonishing that a game released in 2020 would feature such a plot. Granted, gameplay was more crucial to a game's success than the story, but anyway... The demon lord's attempt to conquer the world had resulted in the creation of dungeons across the continent, perilous locations connected to the Demon Realm. The player's role was to accompany the protagonist, Fabian, in recruiting various characters and clearing dungeons.

One of those recruitable characters was the owner of the body I currently inhabited—'Jun Karentia,' a support mage in her mid-twenties with gray hair and cat-shaped scarlet eyes. She was my favorite character in 'The Sacred War'... though, of course, that didn't mean I wanted to become her. It still baffled me how I had ended up transmigrating into the game and possessing Jun, but moving on...

In my original world, the demon lord was advertised as the final boss the player had to defeat to complete 'The Sacred War'—at least for the first playthrough of the game. In reality, the demon lord was a decoy meant to surprise players; in other words, a figurehead. Once the player defeated the primary final boss, who was determined to achieve world domination, the demon lord would be pushed to his limits and go berserk. The player would then witness a hollow ending where the demon lord used his hidden core to turn back time.

But of course, that wasn't the end. This game featured a characteristic that had become increasingly common in the latest generation of games: a hidden ending. To unlock this ending, the player had to embark on a second playthrough. After going through the same storyline with the same characters and facing the demon lord once more, the narrative would take a different turn: Dark Knight Mayer Knox, the former rival of the protagonist, would suddenly make his appearance in the demon lord's castle.

During this encounter, the player would discover that Mayer was the core of the demon lord. To rid himself of the demon lord's curse that lay dormant in his blood, the duke would have to slay the king of evil. However, an unexpected twist awaited—the moment the demon lord perished, Mayer would absorb all of his power. Overwhelmed by the immense demonic energies, he would then become the new lord of the demons.

Only by defeating Mayer Knox— who, upon becoming the second demon lord, would immediately lose control—could the player unlock the true ending.

Therefore, joining Mayer's Dark Knights meant veering away from the main storyline. Moreover, once Mayer assumed the role of demon lord, there was a significant likelihood that the Dark Knights corps would be captured and persecuted as demonic minions, something I wanted no part of!

My ultimate objective was to vanquish the demon lord and then, as one who had fought alongside the champion, live a splendid life in the forthcoming era of peace. Even though aligning with the champion was no longer an option, giving up my planned tranquil retirement was out of the question.

This was why I couldn't simply accept Mayer's offer, despite the bitterness I felt from Fabian's betrayal. His offer, which now seemed like a shining, golden lifeline, would eventually deteriorate into a frayed thread leading to my downfall. My predicament was already dire, and Mayer's presence only exacerbated it, giving me a throbbing headache.

Cold sweat trickled down my cheeks. I had to decline his offer, no matter what... the question was: how? The duke did not strike me as someone who would easily back down. Even now, he stared at me intently, his golden eyes gleaming with the unwavering determination to have me join his expedition corps, using any means necessary.