Koihime Musou - Season 2 Episode 9 Gakushin, Riten, and Ukin, Protect a Village

Ryuubi is really happy about giving her sword back. In the way to return Touka, the party stops to rest in a village. They're mistaken to bandits, then their leaders Riten and Ukin attack them. Shortly after that, the mistake is clear and their other leader, Gakushin, brings a formal excusement to them. They find out Gakushin's group plans to join Sousou's army due to her good impression, but the bandits around there attack them many times and they don't have plans to defeat all the bandits, though. Ryuubi's party decide to help them. Koumei plans to use the Ryuujin-ko (the near lake) to help defeat the bandits (a flood attack using the rain, the bridge, the lake and the riverbed). They build a floodgate due to Riten's construction talent. Following the tactic, a small group attacks the bandits' camp to lure out them. When they arrive the riverbed, Riten will follow Koumei and Ryuubi's signal to open the floodgate to use the water attack. But the large rock falls and halts the water. Ryuubi uses her sword to a lightning rod and the lightning breaks the large rock. Finally, the flood attack is successful. Ryuubi asks Kan-u to be her younger sister, but Chouhi says she only accepts Ryuubi as her older sister, and the bond is built.