Maoujou de Oyasumi Sleepy Princess in the Demon Castle
Syalis is a princess. A really cute one. When she gets kidnapped by the Demon King as a hostage, she's stuck in a castle full of demons, waiting to be rescued by her knight in shining armor. So what does she do? What any of us would. Take a nap—on a pillow she fashioned from her Teddy Demon guards. Duh.