In a future where Mars has been transformed into a water-filled world named Aqua, dissatisfied individuals from Earth now call this new planet home. Resembling Venice from Earth, Neo-Venezia captures the quaint beauty of its predecessor with gondolas gracefully gliding along its canals and charming alleys awaiting exploration. Akari Mizunashi, a young Earthling, embraces Neo-Venezia as her new residence. Determined to fulfill her aspiration of becoming a gondolier guide, known as an Undine, she enrolls in the prestigious Aria Company—an esteemed water touring business in town. Immersed in a serene lifestyle unattainable on Earth, Akari joyfully navigates her days in Neo-Venezia, a place where enchantment and wonders thrive.