Sleepy princess in the demon castle, vol. 1, paperback/kagiji kumanomata

A captured princess just wants a good nights sleep Imprisoned in the castle of the Demon King, all spoiled-sweet Princess Syalis dreams of is a good nights sleepShhh.

Kidnapped by the Demon King and imprisoned in his castle, Princess Syalis is.

She decides to while away the hours by sleeping, but getting a good nights rest turns out to be a lot of workShe begins by fashioning a DIY pillow out of the fur of her Teddy Demon guards and an air mattress from the magical Shield of the Wind.

The princesss hapless demonic guards soon discover that their captive expects to be treated like, well, a princess.

Things go from bad to worse--for her captors--when some of Princess Syaliss schemes end in her untimely--if temporary--demise and she chooses the Forbidden Grimoire for her bedtime reading.