Gema is a perpetually hovering yellow ball-shaped creature with small arms and small circular hands. His face appears upside-down to observers, though this orientation is normal for his species, resembling a simple rubber ball or balloon with minimal features.

He serves as the diligent and serious guardian and caretaker to Dejiko and Puchiko. His frequent nagging lectures, aimed at their welfare, often prove ineffective against Dejiko's rebellious nature, regularly making him a target for her eye beam attacks. Despite this antagonism, he maintains unwavering loyalty and genuine concern for them.

His speech consistently includes the verbal tic of ending sentences with "gema" or "gema gema". His primary capability involves employing a blowgun loaded with tranquilizer darts, though these darts lack significant effect.

Originating from Planet Di Gi Charat before relocating to Earth, his parents Conrad and Johanne are deceased. His family includes two older sisters, two younger sisters, and four younger stepsiblings from his stepmother Teresa. His stepfather Robert is also deceased. Extended family comprises an aunt Cony (deceased), uncle Tatako, and cousins Laurent, Laureline, Lauren, Laura, Lala, Lili, Elly, and Lorelai. He is married to Janie and Jeanne, with sons named Takuya and Kaguya.

Within narratives like the Christmas Special, he participates in group activities such as Piyoko's cruise invitation scheme, demonstrating observational awareness by pointing out Dejiko's hypocrisy. His caretaker role persists in alternate continuities like *Nyo!*, despite Dejiko's continued aggression. He remains absent from the *Winter Garden* storyline. In the visual novel *Di Gi Charat Fantasy*, he fulfills his guardian role within the fantasy setting.