Maoujou de Oyasumi  

Sleepy Princess in the Demon Castle, Sleeping in Devil's Castle, 魔王城でおやすみ, Maou-jou de Oyasumi, MaouYasu, 在魔王城说晚安, Sleeping in Devils Castle

The Demon Lord Tasogares castle is an ominous and terrifying place filled with various monsters. Anyone unfortunate enough to be imprisoned there would undoubtedly be terrified by the horrors that reside within. However, Princess Aurora Suya Rhys "Syalis" Kaymin's situation is different. Despite her circumstances, she remains indifferent and solely focuses on getting a good night's sleep. Since being kidnapped by the demon lord, she has not had a single restful night. To alleviate her insomnia, Princess Syalis makes do with whatever materials she can find in the castle. Whether it be the soft fur of fluffy demonic teddy bears or the silky, blanket-like bodies of ghost shrouds, everything serves as a means to help her sleep peacefully. With so many resources at her disposal, nothing will stop Princess Syalis from getting the rest she needs, not even death itself.