“Please allow me to confirm the reactions shown on Your Majesty’s body.” The Emperor of Yeguk, Baekrim, lost his desire due to poison he consumed as a child. The imperial physician sets out to find a rare herb, but after being injured during the journey, he entrusts his younger sister, Seol-yeong, with serving the emperor in his stead. “I have one request.” “What is it?” “Please allow me to confirm the reactions shown on Your Majesty’s body.” Known as a “ghost emperor,” Baekrim greets Seol-yeong with a beautiful smile and treats her with unexpected warmth. Seol-yeong, despite her role as a stand-in physician, finds her heart wavering more and more…….