Ai Hoshimiya, a first-year Hakuoh Academy student, enters the Space Yacht Club during Marika Kato’s sophomore year. Her short brown hair frames a fringe above brown eyes, complemented by a petite stature distinct from her peers. She dons the standard uniform paired with a pink club hoodie during missions, topped by a white curved hat adorned with ear-like accents. During the Princess Apricot raid, she swaps this for a green-and-white fairy costume with a vibrant red-and-yellow skirt.

Though initially reserved, Ai warms to her clubmates, channeling her passion into piloting and dinghy operations. A middle school solo pilot tournament champion, her innate skill surfaces when she steers the Bentenmaru during a crisis, proving her mettle in commanding large vessels despite her novice status.

In the Nebula Cup, an EMP attack cripples her dinghy’s systems. Undeterred, Ai navigates via memorized constellations—a feat enabled by prior star map study—rejoining the race and securing third place in the club’s internal qualifiers, outpacing Marika.

The *Abyss of Hyperspace* film sees Ai aiding a decoy operation against the Yggdrasil Group. When a tracker jeopardizes the mission, she boards the Odette II to confront adversaries, contributing to the retrieval of the Advaseele from subspace.

Novel-exclusive arcs expand her role: piloting the Odette II through a temporal rift in the Timeslip Arc, further solidifying her spacecraft expertise. Her bond with Marika thrives on mutual trust—Marika relies on Ai’s piloting finesse, while Ai regards her as a guiding mentor.

Ai masters wind-current prediction and navigation systems through relentless simulation drills. During a storm simulation, her steady composure averts a collision caused by a teammate’s error, underscoring her calm under duress.