Yume Okoku to Nemureru 100: Nin no Oji-sama

A normal girl who is transported to the dream world, a place powered by dreams, and discovers she's a princess. She teams up with a rabbit guide named Navi and Prince Avi to awaken 100 sleeping princes, protectors of the realm, who have fallen victim to the dream-eating creatures known as "Yumekui," to save both the dream world and the human world from these threats.