Only the rumble of a motorcycle disturbs the chilly winter calm among the forlorn remnants of a once-thriving metropolis. Its riders, Chito and Yuuri, are the city's final survivors. To pass the time while scavenging ancient military installations for food and components, the two girls wander the wastelands and fantasize about the old world. Chito and Yuuri both battle with the oncoming loneliness, but when they have each other, sharing the burden of being two of the last humans gets a little easier. Their dismal days get a bit lighter with shooting practice, new books, and snowball battles on the icy battlefield, thanks to Yuuri's clumsy exuberance and Chito's steady calmness.