Gema serves as a recurring antagonist in the *Di Gi Charat* franchise, part of the Black Gema Gema Corps. This group relentlessly pursues the kidnapping of protagonist Dejiko, aiming to secure ransom money for their financially troubled home world, Planet Analogue. Princess Piyoko leads the Corps, with Gema operating alongside members Rik, Ky, and Coo.

Hailing from Planet Analogue under Princess Piyoko, Gema and the Corps constantly devise schemes to capture Dejiko, typically involving exaggerated and comically ineffective plans. One notable attempt occurs in the special *Kuchi Kara Bazooka*, where they plot to use Piyoko's powerful "Mouth Bazooka" attack to counter Dejiko's "Laser Eye Beam." Their strategy consistently fails due to the lengthy verbal activation required for the Mouth Bazooka, leaving Piyoko vulnerable to Dejiko's faster attack.

Gema originated in the four-panel manga *Gema Gema*, serialized in *From Gamers*, a promotional magazine for the Gamers retail chain, establishing the character within the foundational *Di Gi Charat* cast.

In the film *Di Gi Charat: A Trip to the Planet*, Gema and the Corps attempt to intercept Dejiko's journey home, employing space battles and disguised traps. Their plans crumble through comedic mishaps or unexpected interventions, like a giant Abarenbou's appearance. The film concludes with the Corps receiving an unexpected invitation to a celebratory party on Planet Di Gi Charat, departing with leftovers.

Gema also appears in the OVA series *Di Gi Charat Theater: Leave it to Piyoko!*, which further chronicles the Black Gema Gema Corps' escapades and their dynamic as foils to Dejiko. Across all media, Gema remains a consistent but minor figure within the antagonist ensemble, defined by the group's collective bumbling and a lack of individual backstory beyond loyalty to Piyoko and Planet Analogue.