The fortress of Tasogare, ruled by the Demon Lord, is a grim and dreadful place, filled with a multitude of monstrous creatures that strike fear into the hearts of those who are trapped within its walls. However, Princess Aurora Suya Rhys, also known as Syalis, remains unperturbed despite her captivity. Her only concern is to get a good night's sleep, a task that has proved difficult ever since she was taken from her kingdom. To solve this problem, Syalis makes use of the materials she finds in the castle. She uses the soft fur of demonic teddy bears and the smooth, sheet-like texture of ghostly shrouds to create a comfortable sleeping environment. The princess has access to an ample supply of such materials, and she is relentless in her pursuit of a sound night's rest. There is no obstacle that can stand in the way of this sleep-deprived princess, not even death itself.