
The Bubuki battle continues aboard the train that's carrying Oubu toward Treasure Island. A beam fired from Arabashiri's Bubuki ring hits Kinoa, causing her own past to replay in her mind and slow her down. Azuma tries to help, but Kinoa stops him, saying she must settle her own score with Arabashiri. So Azuma agrees to just watch, but Hiiragi can't help wondering what Kinoa's relationship with Arabashiri is. What really happened in their past?
Kazuki Azuma returns to Japan after ten years away, only to be chased down by the Bubuki police. He's saved by a childhood friend, Asabuki Kogane, and her right-hand-shaped Bubuki. He then meets the Bubuki users Nono Hiiragi, Ougi Kinoa, and Taneomi Shizuru. Azuma has never even heard of Bubuki, but after learning that he's the user of the "heart" Bubuki, he makes his way to the Buranki prison in Shinjuku's underground to awaken the sleeping Buranki called Oubu.
Azuma stares in stunned shock at Oubu, now reduced to bones, as Hiiragi, Kogane, and the others successfully hold off Matobai. Hiiragi realizes this is the best chance to awaken Oubu and demands the heart Bubuki from Azuma, but Azuma insists he has no such thing. Believing that the heart Bubuki will react if its owner is in danger, he attacks Azuma with Iwatooshi!