Sleepy Princess in the Demon Castle

is a Japanese manga series written and illustrated by Kagiji Kumanomata. It has been serialized in Shogakukan's Weekly Shōnen Sunday magazine since May 2016, with its chapters collected in twenty-five tankōbon volumes as of July 2023. An anime television series adaptation produced by Doga Kobo aired from October to December 2020. Plot The story follows Princess Syalis, a young princess who was kidnapped by the Demon King, and her quest to sleep well while imprisoned. Despite the Demon King's best attempts, the princess turns her kidnapping into a vacation; having grown tired with the stress of a royal life, she is indifferent to the situation. Characters Princess Syalis is a princess who was kidnapped by the demon king and causes chaos in the demon castle while trying to get a good night's sleep. She has been living at the demon king's castle for four years now.