Mercedes and the Waning Moon: The Dungeoneering Feats of a Discarded Vampire Aristocrat (Manga) Volume 3 by Fire head

Now that Mercedes has reached the final floor of Stark Dungeon, she finds herself face-to-face with Schwarz Historie, or “Past Erased.” It's a fierce foe, unlike any Mercedes has encountered before. However, a fragment of truth awaits anyone who can overcome this trial. What will she learn, and what will be her final reward?