An Imagin and one of the main characters on Kamen Rider Den-O.
Voice Actor: Suzumura Kenichi 鈴村健一
Suit Actor: Ogura Toshihiro おぐらとしひろ
Although Ryuutaros is the fourth Imagin to appear from Nogami Ryoutarou, he actually possessed Ryoutarou just before Urataros, using Urataros' possession as a camouflage so no one would notice. He remained hidden inside Ryoutarou so he can be around Ryoutarou's sister, Nogami Airi. He was ordered to possess and kill Ryoutarou by a voice in his head, on the promise of becoming a conductor for a Train of Time when the job is done. The voice is later revealed to be Kai. Ryuutaros is the only Imagin to has his own train ticket (possibly given by Kai), so the DenLiner crew cannot force him off the DenLiner.
His image of a purple dragon is not based on any Japanese legends.
Mind if I ______? Can't hear you!
Ryuutaros has a personality of a kid and likes breakdancing. He is the strongest of the four Imagins, and no one was able to control him at first. He possesses and takes control of Ryoutarou at will and not even Ryoutarou can stop him from doing so. It requires Momotaros, Urataros and Kintaros' joint efforts to stop him from possessing Ryoutarou. He is very fond of Ryoutarou's sister Nogami Airi, and refers to her as his own sister. The DenLiner crew often exploits on this to get him to behave or stop him from killing Ryoutarou. He grows attached to the DenLiner crew eventually, and refuses Kai's orders to kill Ryoutarou. He refers to Urataros as Kame-chan and Kintaros as Kuma-chan, but does not use honorifics for Momotaros and often calls Momotaros "idiot" (馬鹿 Baka).
Ryuutaros likes to draw with crayons and gets mad if others step on his drawings. He was the one to draw the image of the DenKamen Sword, allowing Ryoutarou to henshin into Liner Form. He also like animals, and gets extremely mad when someone hurts them. Ryuutaros likes to break dance and incorporate it into his fighting style. He is able to control others with a snap of his fingers, often forming a breakdancing group around him using this technique.
He wore a headphone when he first revealed himself in the DenLiner, though it is changed to a larger earmuffs later on. Other than going with his hip hop and breakdancing motif, it's possible that he uses those to try to block out Kai's voices in his head.
Ryuutaros gets jealous of Sakurai Yuuto of being Nogami Airi's fiance and tries to kill him at first. The two eventually developed a bitter understanding of each other. Yuuto was the only one to console him when Ryoutarou refused to fight with his Imagins anymore, and when Nogami Airi rejected R-Ryoutarou as her brother.
Kamen Rider Den-O
Out of the four main Imagins, Ryuutaros is the only one that does not come from a "Tarou" legend. On the TV-Asahi Website, it is said that Ryuutaros' form is based on Ryoutarou's image of a dragon. In the Imagin Anime episodes 4 & 25, they slightly discussed the origin of Ryuutaros' motif, stating that Ryuutaros may be based on "Tarou, the Dragon Boy" (龍の子太郎 Tatsu no Kotarō). It's a children's literature written by Matsutani Miyoko and has been made into a movie by Toei, but cannot be mentioned due to copyright reasons.
No matter the origin, Ryuutaros, Den-O Gun Form and DenLiner Ikazuchi's designs are based on a dragon motif.
- As stated by Suzumura Kenichi in the Den-O talk show, Ryuutaros was supposed to be a mystery character, and was not supposed have much screen time or even be around in DenLiner. However, when suit actor Ogura Toshihiro started jumping and moving around DenLiner in Ryuutaros' suit, the staff decided to increase Ryuutaros' screen time on DenLiner. This is evident in that after his first apperance on DenLiner in episode 14, he wasn't seen in DenLiner again until episode 18.