While exploring the items stored in the Outdoors Activities Club room, Nadeshiko Kagamihara spots canned tuna. Assuming its purpose is to distract wild animals, she inadvertently opens a can when Chiaki Ohgaki and Aoi Inuyama arrive, with the former intending to use them to create oil lamps. As they discuss Nadeshiko's Yamanashi background, the trio agree to participate in a stamp rally-an effort to visit and collect stamps at the prefecture's landmarks-to win a year's worth of Minobu steamed buns.