Sora decides to stay until Seikichi builds the firework cannon, with Ginjiro being a killjoy. Sora quickly leaves after a lovesick Shunpei and a watchdog Onui causes more dismay for Seikichi. Ginjiro finds Oise, who faults him for having her fake an abacus dance for the upcoming river festival. Ginjiro later witnesses the white sky beast being attacked by a group of unknown armored men. Seikichi, after seeing Sora using strontium carbonate powder to enhance the coloring of a firework during a demonstration, is finally convinced in helping her build the firework cannon.