Saburō Kōga: 2 works in the original Japanese, with translation

After the earthquake the police ceased to function, and residents everywhere organised volunteer self-defence groups (自警団) to keep watch and patrol. With rumours flying and transport cut off, the atmosphere was one of extreme panic. The night-watch group in the story is a remnant of this.

"切れた草鞋" (worn-out straw sandals) refers to sandals that have been worn through and discarded, a metaphor for something utterly worthless and thrown away. Here it describes treating human sentiment or obligation as being as worthless as a worn-out straw sandal—extreme heartlessness.