In a post-apocalyptic world, Yoko and Airi travel freely on their electric bike, Serow; their destination this time is Hakone.

Their journey takes them from Hakone to Yokohama; they pass by collapsed bridges and see skyscrapers floating in the sea; as the two set out in search of food, an unexpected encounter awaits them.

Yoko and Airi get thirsty on their way to Tokyo, so they make a pit stop at Todoroki Ravine in Setagaya; after they quench their thirst, they walk around empty houses looking for food.