Nathan had started to stuff his backpack with bottled water when the door opened. He drew and turned, anticipating the conflict, and was reluctant to withdraw. However, it was the sensible option. Even silently, by the time it took them to dispatch these walkers, the rest of the horde would be almost upon them, with a limited window for retreat. So he backed up quickly with the others, keeping his eyes open for other zombies lurking behind the shelves.