MTL - Black Bellied Belle: Demon Lord, Bite the Bait Please - Chapter 5 : Associated instrument spirit

In a world where the boundaries between dimensions are thinning, a young man named Kael Ardent is thrust into the Eternal Nexus, a realm where countless worlds converge. Here, the laws of reality are dictated by Aether, a mystical energy that fuels both creation and destruction. Kael discovers he is a Nexus Warden, a rare being capable of manipulating Aether to bridge worlds and command the forces of the Nexus.But the Nexus is not a place of peace. It is a battleground for Eldari, ancient beings who seek to control the Nexus and use its power to dominate all existence. Kael must navigate this treacherous realm, forge alliances with warriors from other worlds, and unlock the secrets of his own latent powers. As he grows stronger, he uncovers a prophecy that foretells the rise of a Prime Warden, a hero who will either save the Nexus or doom it to eternal chaos.

To save a doomed fantasy world, I killed the main characters, then destroyed the game world, and fell into another timeline as the academy's top seat and rival to the protagonist.Now, I'm trying to save the world and steer it towards a better ending…But I'm the final boss.

“You’re the moonlight that lights up the night’s darkness~

Entered the academy in the game.

With unbalancing skills that destroy the balance of the game’s original storyline.