When the nuclear apocalypse wipes out civilization, the only remaining life on Earth will be Chuuya and a load of cockroaches; Dazai believes that with every fiber of his being. It started out as haphazard attempts, the kind that are only meant to maim rather than kill, their attempts on each other's lives becoming more lethal over time; until the inevitable finally happens. Deep in denial, Dazai must come to terms with what he's done, or succumb to his impulses as he attempts to unravel his own mind. (crossposted from ao3)