ただひたすら走って逃げ回るお話

It has been three months since a virus that makes humans go violent spread throughout the world, and the rulers of the earth have shifted from humans to the infected. The police and self-defense forces have been destroyed, and government agencies have ceased to function. Civilization has collapsed and the few survivors are living in hiding, while a young boy survives alone in a ruined city. He spies on the infected and retreats to one of his rooms for the rest of his life. One day, however, the boy’s life is changed forever by a girl he meets.