MTL - History’s Strongest Senior Brother - ~ 1815. Wind and water turns, millennium new weather

Transmigrated to the world of Demon Slayer, only to become a swordsmith?“Then I'll forge the strongest Nichirin Blade!”With each hammer strike against the iron ingot, a notification appeared...[Impurities -1]After a hundred refinements, another notification...[Constitution +1]Upon completing the weapon, a final notification...[Current Weapon Sharpness Level: 1][Forgemaster: Strength +10, Constitution +10, Agility +10, Speed +10][Reward: Sun Breathing Technique!]“Maybe... I should become the strongest swordsman after all?”

Talent.As a demon born into a prestigious family like the Tenebris, Cale lacked nothing, except talent.Talent, to surpass his twin sister, who was better than him in every way.Talent to earn the approval of their mother, the cold and ruthless Matriarch.It wasn’t mere rivalry; his very life depended on it.But, no matter how hard he trained or how low he stooped, using forbidden methods to grow stronger, he never succeeded. He couldn’t awaken his bloodline, nor defeat his sister in a single duel.“Just give up already. You’re only making it more painful for yourself,” she would say every time.He was pathetic, and he knew it.But giving up on life was never an option.“One more time... I’ll try it one more time.” That was how he always responded to her scorn.Was it ego? Or a desperate desire to prove everyone who waited eagerly for his downfall wrong?Cale didn’t know. But he always stood up again.No matter what they said, he refused to surrender.Not to his mother.Not to the world.Not even to his sister.If the world stood against him, then he would crush the world.-------------------------“Wow. That’s an incredible backstory for a villain.”I flipped through the worn pages of an old book, my only functional eye open wide.“But where did this come from? It wasn’t here before.”I’d read this romance fantasy novel back in my childhood, and as far as I remembered, Cale Tenebris never had a backstory.“Did I grab the wrong book?” I tilted the cover to check the title.[Curse of the Crown]It was the same one.“Did I skip this chapter before?... Whatever.” I shrugged, turning the page again as I slowly lost consciousness.And then I died.

A broken man who ended his own life finds himself reincarnated into the game he used to play. However, instead of becoming the protagonist or a powerful antagonist, fate places him in the role of a minor villain—a mere stepping stone for the protagonist in the game's first arc.