When Kokone sleeps she dreams of Heartland, a place full of technology and warring machines, where she's the Princess Ancien who possesses magical powers. But when events in her dreams and real life start to intersect, Kokone has to run from bad guys in both worlds. Will her dreams provide a way out, or get her into deeper trouble...? (Source: Yen Press)

Hirune Hime: Shiranai Watashi no Monogatari was published in English as Napping Princess: The Story of the Unknown Me by Yen Press on June 5, 2018. It was also released in Brazilian Portuguese by NewPOP Editora on September 25, 2019.