A dark cloud containing the demon Nokosaregumo appears over a village and the villagers hurriedly prepare woman as a sacrificial bride to appease it. As Hyakkimaru and Dororo see the bridal parade travelling up the mountain, Saru, a wild boy, tries to stop the sacrifice. After Saru tells them the story of Nokosaregumo and the kind woman he considers his sister, Dororo and Hyakkimaru agree to exterminate the demon. A dark cloud envelops them, and Nokosaregumo appears as a large centipede. However, Hyakkimaru is unable to differentiate the demon from the cloud as they both show red to his vision and it swallows the woman. Dororo and Saru devise a plan to create an explosion using the sulphurous gases emitted by the mountain which sets the demon ablaze but has little effect. Dororo then jumps on Nokosaregumo`s head and calls to Hyakkimaru, enabling him locate and attack the centipede by sound, destroying it. The dark cloud dissipates and Hyakkimaru, Dororo and the woman (who was swallowed whole and not yet digested) fall into a spring. Saru is relieved to find his sister alive and agrees to move into the village with her. Hyakkimaru regains his sense of smell and addresses Dororo by his name for the first time.