|This article is about a/an kaijin in Kamen Rider Black RX.|
Gynaninpo is an ape monster that leads the Devil Beastman Ninja Corps.
After the Devil Beastman Ninja Corps attacked a mountain village and captured its inhabitants, they and Gynaninpo attacked Kohtaro and Reiko and Goro while they were in the woods though they were saved by Joe. Joe infiltrated the building that Bosgun had the prisoners in by disguising himself as a Devil Beastman Ninja, until his coughing gave him away to Bosgun and Gynaninpo. Gynaninpo took out Joe and assumed his form. Gynaninpo sent the Devil Beastman Ninja Corps to attack the place where Kohtaro and Reika found the kids taking refuge. Kohtaro fought them until "Joe" defeated them and led them to where Bosgun has the prisoners. After Kohtaro found the real Joe, Gynaninpo shed his disguise. Bosgun revealed his plans to Kohtaro and left as Gynaninpo and the Devil Beastman Ninja Corps fought Kohtaro. Kohtaro transformed into BioRider and freed the prisoners. BioRider and Gynaninpo fought outside as BioRider destroyed his Devil Beastman Ninja Corps. He then called for Mach Jabber and charged him. Gynaninpo climbed a cliff and attacked BioRider, but he turned into water, attacked him, and knocked him off the cliff. BioRider reverted to Kamen Rider Black RX and used his Revolcane to disarm Gynaninpo before destroying him.
Gynaninpo wields an extending staff in battle which he can shoot beams from. He can also assume the form of anyone he chooses.