The Crimson Heir，My Brother's Bride

In an era where peace between humans and vampires is maintained through tributes, Princess Elias disguises herself as a man and takes the place of the crown prince—offering herself as the sacrificial bride to the Vampire Emperor Noctis, in order to save her sister. She soon discovers that she possesses a rare bloodline capable of suppressing the Emperor's ancient curse, and gradually earns Noctis's trust and love.