They Said I Was Useless Without Magic, So Why Am I the Next Duchess?

Due to her low magical power, Count’s daughter Algerieta is forced by her family to take on the harsh task of caring for dragons. As if that weren’t enough, she’s arranged to marry an elderly duke—but before that can happen, his grandson Margus delivers news of the duke’s death, leaving her on the verge of unemployment! That’s when Margus says, “Then just marry me instead,” and suddenly, she becomes his wife!? Tasked with caring for his beloved dragon, Algerieta assumes it's just a contract marriage… but Margus starts treating her like his real wife!?