A young couple, Mayu & Kota, travel to a mountain cabin for a getaway. They arrive late and find that the cabin has no water. When they contact the manager, they are told that they must wait until the next morning for repairs, because no one in that area goes out at night -- people are afraid to. Kota ventures out to get Mayu something to drink and comes across an ancient vending machine. The couple both drink the unfamiliar brand of soft drink and suddenly find themselves behaving very strangely.
