Mercedes and the Waning Moon: The Dungeoneering Feats of a Discarded Vampire Aristocrat

Reborn as a vampire, Mercedes Grunewald has won the lottery of life. She's strong, quick, beautiful, and even a noble. Technically a noble, that is. Her mother is merely a concubine, and her father shows no interest in the family he's shunned to the countryside. Knowing the comforts of her life will be lost once he chooses an heir, she resolves to take matters into her own hands. At just ten years old, she begins a life of dungeon crawling. But what will she find for herself out there in the dungeons? In her past life, she died unfulfilled, but this time, she's set on achieving a different fate. Whether it be fame, fortune, or simply a reason to live, this time, her moon will be full.

(Source: J-Novel Club)