In the bustling city of Neo-Tokyo, Aiko Hoshino is a spirited teenager navigating the challenges of high school. Surrounded by rapidly advancing technology, Aiko finds comfort in reading sci-fi novels, which inspire her vivid imagination. Though she's an average student, her teachers are amazed by her creative drawings and unique perspectives. Aiko's curiosity often leads her to explore hidden corners of the city, where she indulges in her passion for stargazing despite the luminous skyline. Raised by her single mother, Aiko learned resilience at a young age and harbors dreams of becoming an astronaut. Her journey unfolds as she discovers an ancient, mysterious book that hints at a forgotten world beyond Earth, sparking an adventure that transcends her wildest dreams.