Charlotte, the daughter of a duke, is overjoyed when her marriage to Kiel, the captain of the knights, is arranged. She dreams of a happy married life, but her dreams are shattered when Kiel suddenly tells her, "I cannot love you." Having grown up without knowing parental love, Kiel doesn't understand what love is, which is why he says he can't love Charlotte. In response, Charlotte proposes, "Then let me teach you what love is!" And so begins a tender and heartwarming love story between a clumsy knight who doesn't know love and a duchess overflowing with affection.