Cairo is a robotic assistant serving Dr. Shinichiro Izumi at the Daimobic Base, handling technical support and operational tasks for the scientific team. The character possesses a stubby, humanoid mechanical design primarily red with yellow accents, featuring large round eyes and visible teeth that create an expressive appearance. Cairo maintains a consistently cheerful and talkative demeanor, frequently offering wisecracks or sarcastic commentary during operations. This personality generates recurring humorous situations within the narrative, particularly through interactions where the caretaker Okane frequently harasses or scolds Cairo. The character also engages comically with Okane's nephew Genta in later episodes.

No substantive character development or background expansion occurs throughout the series; Cairo maintains a consistent supportive function without narrative evolution or revealed origins. The character does not appear in spinoff media or alternative adaptations beyond the core series. In international releases, Cairo underwent name localization, becoming "Wilbur" in the Philippine English dub.