Rayleigh transmigrated into an imperial princess who can’t sleep because of black magic. The only way she can sleep is by touching Ian, the male lead and the master of the original book. Well, there’s a problem. First, Ian is the duke of the enemy country. Second, Ian doesn’t easily show his kindness to people because of his past trauma. Rayleigh is forced to hide her identity and infiltrate Ian’s castle as a “personal maid.” Rayleigh, who is looking for Ian’s niche every night, and Ian comes to suspect her identity. Hiding different innermost thoughts, the two are getting closer, and the black wizards are threatening them……… Can Rayleigh cure her insomnia? A healing romance between a princess disguised as a maid and a traumatized Duke.