Loneliness drives an introvert to write a letter to the girl in the apartment across the hall. He is anxious. Reclusive. Desperate for a friend. The apocalypse interrupts this attempt at human contact.
Now he watches out the window as the world gets cut to pieces by plague and riots. Buildings burn. Pedestrians vomit blood.
Soon the bodies line the streets. Rumors of zombies spread. And then the power goes out.
Getting to know someone could be harder than he thought, let alone surviving in a post-apocalyptic wasteland.
He might even need to leave the apartment.