Harold Katori is the pilot and navigator for the United Planets Space Force destroyer *Soyokaze*, holding the rank of First Lieutenant. He displays a consistently calm and well-mannered demeanor. Katori possesses significant confidence in his piloting and navigating skills, adeptly handling large vehicles under pressure and executing sharp evasive maneuvers during enemy fire. His peaceful personal philosophy is reflected through the frequent incorporation of Buddhist sayings into his speech and his dedication to meditation during spare time. This temperament generally fosters harmonious relationships with most crew members.

Katori develops trust in his commanding officer, Captain Justy Ueki Tylor, earlier than many other crew and follows Tylor's orders without extensive questioning relatively quickly. In informal gatherings where female crew discuss male colleagues, he is typically excluded from criticism and sometimes participates in these conversations.

Katori maintains careful grooming habits focused on his appearance and bodily care. He is consistently seen with neatly styled blonde hair. However, the final episode reveals this blonde hair is actually a wig, concealing his baldness. Information regarding his background story, further character development, or appearances in other official media such as OVAs, movies, or spin-offs lacks concrete detail in the available sources.