|Human Partner||Akiyama Ryo|
|Voice Actor||Seta Ikkei (世田 壱恵)|
|Ultimate||Justimon: Accel Arm (with Akiyama Ryo) |
Justimon: Blitz Arm (with Akiyama Ryo)
Justimon: Critical Arm (with Akiyama Ryo)
Before Akiyama Ryo met the Tamers, in the desert plain on the Digital World, Ryo and Cyberdramon fought Megadramon. With Ryo hiding behind a rock, Cyberdramon hit Megadramon with his Cyber Nail while telling them to bully a Digimon who could fight back instead of destroying defenceless villages. Megadramon told him that no one could defeat them and shot a cliff with their Darkside Attack (Genocide Attack), causing an avalanche to fall on top of Ryo. Cyberdramon blocked the avalanche with his body, causing both of them to be buried, while Megadramon took the chance to leave while laughing. Cyberdramon was knocked out, causing Ryo to break down, thinking there was no way out and realizing he was tired of all the fighting. His memories of how it all began came back at that point.
After Moon=Millenniummon (Moon Millenniumon) sent Ryo to the ancient Digital World while he travelled to the future, Ryo met Monodramon and ENIAC, the world's first computer, who taught him about the existence of multiple Digital Worlds and Earths and how Moon=Millenniummon was desperate to conquer them all. ENIAC then sent Ryo and Monodramon to the future to face Moon=Millenniummon in his final digivolved form: Xeedmillenniummon (Zeed Millenniumon), who Monodramon faced by shooting beams from his hands. Monodramon then forced a DNA Digivolution (Jogress Evolution) between himself and Xeedmillenniummon after realizing that it was the only way to defeat him. Together, they became Cyberdramon, and then he and Ryo ended up on an alternate Earth where Digimon was simply a TV cartoon and a card game.
In the present, as Cyberdramon woke up and freed himself from the rocks, Ryo explained that the part of Cyberdramon that was Xeedmillenniummon made him hard to control so he had to bring him to the Digital World they now lived in. However, he couldn't go on any further. Cyberdramon rescued Ryo and told him not to give up when he was around.
With his spirits renewed, Ryo got on Cyberdramon's back and they flew away to find and get revenge on Megadramon, who they found as he was destroying a Mushmon village, and immediately slashed them then shot them with a beam from his hand, finally defeating them. The Mushmon then hailed Ryo and Cyberdramon as heroes and invited them to a feast, which made Ryo realize that they needed to protect the weak and innocent of the Digital World, which became Ryo's true purpouse.
Monodramon was the first Digimon that Akiyama Ryo met after falling into the past after his last battle with Moon Millenniumon. He became Ryo's newest Partner Digimon at the request of ENIAC. However, during the fight against Zeed Millenniumon, Monodramon forced a Jogress between the two.