Akugyaku Seijo desu ga, Aisuru Danna-sama no Oyaku ni Tachitai desu.

A saint who lost her memory drastically changes from a cruel and ruthless tyrant to a husband-loving wife! When Charlotte wakes up, she has lost all her memories, and the power that made her a "rare saint" has been blocked. But she doesn't mind, because her new husband, Oswald, is too good-looking…! "I think I fell in love with you at first sight!" "I'm sorry, but I hate you." Apparently, the Charlotte of the past tormented people with her cruel behavior. If that's the case, she will try to hide her amnesia and do her best to become a good person! A suspenseful romantic comedy between a clumsy genius mage and the cruel saintess who loves him! (Source: Ichijinsha Novels, translated)