Upon entering the forest, Maruyama has José whistle since he is apparently the only one who can, while Paifu practices his whistling since José will eventually get exhausted. José, instead of getting fatigued from whistling, suddenly falls ill to the Monster Flu as well. Their fear of the monster finding them becomes a reality and they are attacked by the forest monster Baroaba. Maruyama holds his own against the behemoth and tells Paifu to start learning how to whistle immediately before they are killed. Although several attempts had been unsuccessful, Paifu finally prospered in whistling and Baroaba is literally downsized by the sound, proving the weakness true, and is pounded by Maruyama. Before Maruyama finishes him off, he discovers that Baroaba only attacks to protect the forest's rare wildlife; Baroaba apologizes for the misunderstanding and decides to help them get to their destination, the witch's house.