Futei no Ko wa Chichi ni Urareta Totsugisaki no Nariagari Danshaku ni Shinka wo Miidasareru: Tensai Madougushi wa Kurokami no Reijou wo Dekiaisuru

Born as the child of her mother's infidelity, Loretta has lived her life isolated and scorned. Until one day when Loretta is offered a chance to marry a man. It is Bartol, a man of common birth, who was granted a non-hereditary noble title from his accomplishments. Loretta thinks he is only courting her for her "noble birth," but he seems to appreciate her talents, and now she's not so sure… Bartol treats her like a lover, and Loretta is attracted to him, but at the same time she is still confused about their true feelings…

(Source: ES Luna, translated)