Manga follows bored princess waiting for rescue

Viz Media announced at its Anime Weekend Atlanta panel on Friday that it has licensed Kagiji Kumanomata's Sleepy Princess in the Demon Castle (Maōjō de Oyasumi) manga and plans to release the first volume in summer 2018.

Viz Media describes Sleepy Princess in the Demon Castle:

Sshhh! Princess Syalis is trying to get a good night's sleep. Some shut-eye. Forty winks. Catch some Z's. Long ago in olden times when people and demons lived together in—well, disharmony, really – a demon king kidnaps a human princess and imprisons her in his castle. Bereft, the princess's subjects beat their chests in anguish…until a hero arises to spearhead Project Rescue Our Princess! While waiting for her knight in shining armor, what's an imprisoned princess to do …? Teddy-bear guards with bat wings are all very well, but her dungeon cell is bo-o-o-ring! So, she decides to wile away the long hours by sleeping. Now if only she could get comfortable…and didn't suffer from insomnia…

Kumanomata launched the ongoing manga in Shogakukan's Weekly Shonen Sunday magazine in May 2016. The fourth volume shipped in Japan in July and the fifth volume is slated for October 18.