Kao ga Miwakerarenai Hakushaku Reijou desu ga, Akunin Koushaku-sama ni Dekiai sareteimasu @comic

As the daughter of a count, Sarah is unable to socialize and is ostracized by aristocratic society because she has a condition which prevents her from recognizing faces. She is despised by her family and marries the infamous "Duke of Evil" as a substitute for her sister. Calyx is feared as an unfair husband, but he is actually the complete opposite of that! She received a gift of a custom-made dress and a first date holding her hand with a kind word that made her bewildered. For the first time in her life, he treated her like a princess, and the burn mark on his face, which everyone abhors, became the only mark that could distinguish him from others and endear her to him. This is a sweet Cinderella story of an unfortunate young lady who finds her place in the world, doted upon by the "evil duke!" (Source: TO Books, translated)