Yoko is a work depicting the training records of genuine masochistic women who volunteered for discipline at an SM secret circle. The protagonist, Yoko, is a housewife in her mid-thirties, married with three children. She actively serves on the PTA at her daughter's junior high school, yet behind this ordinary facade lies a lustful wife whose masochistic desires were awakened through her husband's perverted training. Following her husband's orders, Yoko steps into the SM secret circle, gradually drawn into a new world of discipline. Her tense expression as she confesses, "I've come because my husband commanded me," realistically captures the collapse of balance between her masochistic desires and daily life.