Chito and Yuuri, two girls riding a Kettenkrad half-track through the ruins of a dead civilization, scavenge for food and fuel across a multi-layered city that stretches endlessly upward. Chito reads salvaged books and keeps a diary; Yuuri eats whatever she finds and carries a rifle she rarely fires. Their quiet routine of cooking rations, bathing in snowmelt, and arguing over whether chocolate or cheese matters more plays out against empty factories, silent railways, and the occasional autonomous machine still performing tasks for people who no longer exist.