The Black Gema Gema Gang is an evil gang who try to kidnap Dejiko.
Piyoko (full name Pyocola Analogue III)
Piyoko is eight years old. She is the Princess of planet Analogue and leader of the Black Gema Gema Gang. Her parents left her in Rik, Ky, and Coo's care until she is thirteen because they are embarrassed to show their faces when their attempt to take over planet Di Gi Charat failed. She had to flee to earth because she blew up a city and couldn't pay for repairs. Piyoko's dresses similar to that of a nurse's uniform, but in black and white colors like a panda. She ends her sentences with "pyo" (although certain manga publications depict this as a squeak). She has an attack similar to Dejiko's Laser Eye Beam called Upchuck Bazooka which is a beam that comes from her mouth, but whenever she attempts to attack Dejiko with it, she more often than not gets attacked herself.
Rik is 26 years old and the General of the Black Gema Gema Gang. He plays the role of the veterinarian of the doctor trio. He takes pride in his profession and loves animals. As a result, Rik has many animals around him. The animals include Bun Bun and Amaenbou. As the gang considers themselves a "family", Rik considers himself as the "Daddy".
Ky is seventeen years old and the Lieutenant General of the Black Gema Gema Gang. He is a dentist and always worries after Piyoko. Ky makes sure that Piyoko practices proper dental hygiene. As the gang considers themselves a "family", Ky considers himself as the "Mommy", even though he is a male. He seems embarrassed by the title.
Coo is thirteen and the Major of the Black Gema Gema Gang. He is the physician of the group. He is Piyoko's childhood friend and is closest to her. Sometimes if food flies through the air he will jump up and catch it in his mouth in a dog-like manner. As the gang considers themselves a "family", Coo is considered the "brother". However, Piyoko thinks she is older than him, although she is only 8 while he is 13.
Nazo Gema is Gema's counterpart in the Black Gema Gema Gang. Like Gema, it is round and floats in the air, but instead of being yellow, it is black. It also has large spooky eyes and red lips. It ends its sentences with "Geba".