Momotaros

Momotaros (モモタロス Momotarosu?) is one of the main heroic Imagin in the series Kamen Rider Den-O, and one of the Taros. As Ryotaro Nogami's first Imagin ally, he allows him to use Den-O's Sword Form. Momotaros eventually becomes the representative of the Den-O series, becoming Den-O himself.

History
Among the hundreds of Imagin that arrived to the year 2007, Momotaros entered the body of Ryotaro Nogami but unable to set up a contact as he is forced to possess Ryotaro when he is attacked by Tetsuo. But after Ryotaro mentally restrains him, Momotaros learns that Ryotaro is a Singularity Point and helps him as Den-O to defeat the Bat Imagin. Admitting he does not remember their mission, Momotaros actually prefers fighting for his own whims. Though Ryotaro gives him his name rather than a desire to fulfill their contact, Momotaros eventually grew to respect the human as well as the other Imagin they are partnered with. In time, Momotaros begins to take his mission as member of the Den-Liner to protect time to heart.

In the Den-O series finale, due to Kintaros granting Ryotaro's unintentional wish for the Taros to stay by his side, Momotaros and the others are able to be present alongside Ryotaro for the final battle with Momotaros accepting Ryotaro's actual wish to fight with him to the very end. After the battle ended, with his existence assured, Momotaros was distant and silence over parting ways with Ryotaro, only to jump to the window at the last second to say goodbye to his friend while promising to meet again as the Den-Liner departs back into the timestream.

That promise is kept during the events of "Final Countdown" when Momotaros is stunned to be fighting Ryotaro while he's possessed by the Ghost Imagin, nearly getting himself killed to free his friend as they fight together against Shiro with Ryotaro's grandson aiding them. Later, he becomes a hot-blooded member of the Den-Liner Police that is formed to battle Negataros. Though Negataros was destroyed, Momotaros keeps the new group together as he sees being a cop as a cool thing.

Decade and Cho Den-O movies

When the recently de-aged Ryotaro leaves to investigate the Oni disturbance in the past, Momotaros loses his physical form and memory as he possesses Yusuke Onodera, allowing him the ability to transform into Den-O Sword Form. However, Momotaros finds himself being attacked by Daiki Kaito who wants Den-O's powers. But when he teamed up with Tsukasa Kadoya, Momotaros regains his memories and physical form while Kamen Rider Decade acquires the Den-O Kamen Ride, Final Form Ride and Final Attack Ride Cards.

Though Decade thought he solved the issues in the main rider continuity (Den-O's world), time was still awry as Momotaros gets sent to the past in the Oni War, which the Den-O team and Decade fight in to ensure that the Oni from years past are exterminated, as history says. Sometime later, the Den-Liner gang face Daiki again when he uses them to steal a treasure in the past.