Yasuko

Tetsuo Tsutsumi's ex-wife. They married more than 20 years ago, not long before the Nejima Murders occurred. They divorced 4 years ago due to Tetsuo's workaholic nature, with Yasuko taking custody of their daughter.

Yasuko suffered a miscarriage in the first few years of their marriage. Soon after, Tetsuo took in and adopted baby found at the site of the Nejima Murders, and the pair raised her as their daughter Ayame Tsutsumi. Following the divorce, Yasuko and Ayame retained their maiden name of Tono.