Endymion Kirian was once a great host. When he was a child, he met a knight by chance who gave him a recommendation letter, inspiring him to become a knight. With a strong determination to become a knight, Endymion joins the knight order called the ‘Swallow Knights.’ However, once he entered the knight order, he realized that it is different from the others. The story unfolds as it explores the adventurous journey of Endymion, a former host who becomes a knight.