HistoryLike many Ayakashi, Doukoku is born on the Sanzu River and took residence on the Rokumon Junk. Originally, Doukoku was in a state of rage all of the time until he heard the music of Usuyuki and forced her into servitude when she was reborn as Dayu Usukawa. Two decades before the series, Doukoku targeted the Shiba House's previous Shinkengers, making it his goal to completely eliminate the Shiba House's 17th head so no one would be able to stop him. However, while fighting the seventeenth head of the Shiba House, he was sealed away as the previous Shinken Red died.
But as the Shiba seal was incomplete, Doukoku was able to revive by the time of the next generation. To reach his goal again, Doukoku sends out Ayakashi to terrorize humans so the Sanzu River can overflow its banks into the mortal realm and enable him to unleash his full fury as he is more dependent on the Sanzu River's waters than the other Ayakashi. Learning of the seal placed on him, Doukoku briefly changes his plans to target Takeru as the death of the Shiba House would ensure that he would never be sealed again. But when that plan failed, due to Juzo Fuwa's own agenda, Doukoku has his forces carry on the original plan without giving wind of this knowledge to any Ayakashi with his own agenda. During the summer while in a comatose state that leaves him open to his enemies, Doukoku manages to suppress his magnified power to punish Gozunagumo for his attempted usurping by turning him into a mindless monster. Later, after Dayu ran off on him when he damaged her shamisen, Doukoku makes an alliance with Akumaro Sujigarano before learning of his true colors and risking his life to enter the mortal realm and repair Dayu's shamisen after driving off Akumaro and defeating Shinken Red. Shitari was able to save Doukoku and place him at bottom of the Sanzu River to fully soak in the rivers.
But after the Shiba Clan true's eighteenth head is revealed, Doukoku's followers attempt to speed up his awakening by increasing the amount of suffering until Dayu uses Shinza's anguish to bring Doukoku back to the mortal realm. After absorbing Dayu's energy to heal his body, Doukoku gains immunity to the Sealing Character and can now endure being in the mortal realm without drying up. As a result, Doukoku overpowers the Shinkengers before bringing the Rokumon Junk into the mortal realm when the Sanzu River floods the city. Thinking he had broken the Shinkengers' spirits when they attempt to defeat him, Doukoku is immobilized before Shinken Blue delivers the final blow. Assuming his second life, Doukoku overpowers Samuraihaoh, blasting it and throwing off its components until only Shinkenoh remains, then impales it on his sword. However, the Shinkengers take advantage of the events and mortally wound him before he explodes. He attempts to take the Shinkengers down with him, but this fails as they survive the explosion.
Doukoku is later revived during the events of the Super Hero Taisen films, the first as a member of the Dai-Zangyack. He is seen fighting GaoBlack, and the Dairangers during the final battle, though his fate was unknown.
He also revived in Super Hero Taisen Z with Space Reider and a few other past enemies, including his servant Dayu and his monster Chinomanako. They were giving the Gokaigers, Go-Busters, Meteor, Fourze, OOO, and Beast a hard time, until Akaranger and Ichigou showed up with reinforcements to even the odds. Doukoku was seen fighting HurricaneRed and Kamen Rider X. He and the others were destroyed when everyone lined up and used their finishing attacks.
Doukoku is very cunning, cocky, wicked, heartless, diabolical, manipulative, uncompromising, temperamental, unscrupulous, egotistical, detestable, dangerous, egocentric, possessive, merciless, arrogant, hateful, greedy, nasty, and evil. As an embodiment of rage, he is in a constant state of it, which can only be soothed by sake and the music played by Dayu on her shamisen. He is easily vexed, furious, irritated, aggressive, obstreperous, uncontrollable, destructive, intimidating, opprobrious, detestable, repugnant, sadistic, violent, quick to aggravation.
- Master Xandred - Power Rangers counterpart in Samurai.