"Napping Princess" is a 2017 anime film directed by Kenji Kamiyama, blending elements of fantasy, science fiction, and coming-of-age themes. The story unfolds across two interconnected worlds: a near-future Japan and a fantastical dream realm called Heartland. The protagonist, Kokone Morikawa, is a high school girl living in Okayama Prefecture. Her life takes a dramatic turn when she begins experiencing vivid dreams about Heartland, a magical kingdom where she is a princess named Ancien. In these dreams, she possesses the ability to bring machines to life, a skill tied to her family’s mysterious past.

In the real world, Kokone’s father, Momotaro, is arrested for allegedly stealing proprietary technology from a powerful corporation, Ichiro Oshiyama. This event triggers a series of revelations about Kokone’s family history and her father’s involvement in the development of autonomous driving technology. As Kokone investigates, she discovers that her dreams of Heartland are not mere fantasies but are deeply connected to her father’s work and a prototype AI system called Heart. The line between reality and dreams blurs as Kokone uncovers the truth about her family’s legacy and the role of Heart in shaping both worlds.

The narrative alternates between Kokone’s real-world struggles and her adventures in Heartland, where she battles against the tyrannical King of Heartland, who seeks to control the kingdom’s magical technology. In Heartland, Kokone is aided by her childhood friend, Morio, who also exists in the real world as a mechanic and ally. The dual-world structure serves as a metaphor for Kokone’s journey of self-discovery and her efforts to reconcile her identity across both realms.

As the story progresses, Kokone learns that Heartland is a manifestation of the AI system’s virtual environment, created by her father to preserve memories and emotions tied to their family. The climax intertwines the fates of both worlds, with Kokone using her unique abilities to confront the corporate forces threatening her family and to restore balance to Heartland. The film concludes with Kokone gaining a deeper understanding of her father’s sacrifices and her own role in bridging the gap between technology and humanity.

The main characters include Kokone Morikawa, a determined and resourceful protagonist; Momotaro Morikawa, her enigmatic father with a hidden past; Morio, her loyal friend and mechanic; and Ichiro Oshiyama, the antagonistic corporate figure whose ambitions drive much of the conflict. The film’s narrative explores themes of family, memory, and the ethical implications of technological advancement, all while maintaining a balance between its fantastical and real-world elements.