Sayaka Murata in a Tokyo convenience store similar to the one where the main character in her novel works.Credit...Kentaro Takahashi for The New York Times TOKYO — Keiko, a defiantly oddball 36-year-old woman, has worked in a dead-end job as a convenience store cashier in Tokyo for half her life. She lives alone and has never been in a romantic relationship, or even had sex. And she is perfectly h