Imo Kusa Reijou desu ga Akuyaku Reisoku wo Tasuketara Kiniiraremashita

Agnes, a noblewoman was ridiculed in the social circles for being unfashionable, happened to help Nazelbert, the duke's son, who had been betrothed to the Princess. However, the Princess saw this and ordered Nazelbert to marry Agnes instead as punishment. Isn't it terrible to marry that girl as a punishment? Look, he seems to hate it too. Wait, he doesn't? This is a story about an unfashionable lady and a duke's son, who grow closer to each other.