Obito no Hime to Kubinashi Kishi

The kingdom of Formont is located at the heart of the continent. Charlotte, the grandson of Joseph, the founding hero of the country, is the youngest princess of the kingdom and a book-loving recluse. She hardly ever shows herself and has failed many matchmaking attempts, but when her father, the king, orders her to go hunting with Albert Horseman, the feared “headless knight,” she is forced to take on a new challenge...? A new kind of royal mystery between a reclusive princess and a fierce knight! (Source: Hana to Yume, translated)