Undercover Butler to the Grand Duke

A year after dying on the battlefield, a knight awakens in a new body in the territory of Grand Duke Vallot, her greatest enemy. Forced to remain in his estate, she eventually becomes the grand duke's one and only butler, handling everything from household affairs to fighting assassins. While she plans to endure for two years and return home with the grand duke's head, she unexpectedly earns the trust and affection of everyone around her, especially the grand duke himself.