Read the title! It's a X Reader Story for Final Fantasy Fans!

Alucard becomes aware of the enigmatic entity whose presence surges through the entirety of the castle: it's present in the very last diminutive crack, every crevice and nook and cranny, in the frigid stones stacked to rise to impressive walls, to even the loose tendrils of worn tapestries... but he's yet to be enlightened on the nature of it.