Nigashita Sakana wa Ookikatta ga Tsuriageta Sakana ga Ookisugita Ken

Due to her incredible athletic skills, Maria "Mimi" Annovazzi has been trained her entire life to inherit her family's duchy. However, the birth of her younger brother makes this unnecessary. No longer the heir, Mimi has to settle down as soon as possible, but none of the kingdom's good marriage prospects remain. She decides to travel to a neighboring country and transfer to the royal academy in hopes of finding a husband. Aida Amethis, a distant relative and Mimi's best friend, agrees to help her.

Her trip turns chaotic when the future crown prince and Aida's fiancé, Renato di Rubini, mistakes Mimi for Aida and annuls his non-existent engagement to her. He planned to free Aida from the arranged betrothal so she could be with the man she actually loves instead. Although the misunderstanding is cleared, Mimi worries about her reputation after the scandal, so she asks Renato to help her find a suitor. Unbeknownst to her, Mimi's sunny attitude and fighting prowess capture the attention of the biggest catch in the whole kingdom: Renato himself!