Gozo Aida rescued Aika Sumeragi from a catastrophic earthquake that claimed her parents, subsequently raising her himself. He established K2 Corporation, building a salvaging operation focused on cost-effective services. Acting as Aika's primary mentor, Gozo trained her in salvaging skills and actively supported her early career development, though he maintained a protective stance due to their shared history. His guidance continued through her attainment of a C-class salvager license and her initial missions.

Gozo supplied operational support during Aika's missions, maintaining aircraft and intervening in critical situations. He occasionally pursued karaoke for recreation and once demonstrated unexpected combat proficiency, incapacitating multiple assailants while intoxicated. Across subsequent series, his role as Aika's guardian persisted, with ongoing involvement in both her professional activities and personal development.