Meldion Koushakuke no Waka Fuufu wa Sukoshi Kawatteiru.

A woman who was Japanese in her past life and now lives as the daughter of a count dreams of a simple, low-key existence. At a ball, she meets the son of a powerful duke, who becomes interested in her after she does not fall for his charm. She tries to avoid the typical romantic tropes but accidentally reveals her past-life memory, leading the duke's son to pursue her with increasing intensity. The story follows their relationship as they navigate aristocratic life in another world, both having been Japanese in their former lives.