By mere chance, the protagonist was reincarnated as the strongest character who doesn’t even appear in the game.
Even though they were reincarnated into the Japanese RPG “Neon Light,” the protagonist ends up as a character with ridiculously overpowered specs who isn’t part of the game’s storyline. They choose to live quietly so as not to interfere with the flow of the story, but unbeknownst to them, the world begins to twist and turn around them.