Female Occupant of No. 71

Female Occupant of No. 71 inhabits a dwelling with Male Occupant and Male Minor. Their lives are harmonious–or so it appears. Female Occupant of No. 71 remembers things that others have been encouraged to forget. How does she know what she knows? Is the past worth remembering? The accumulation of knowledge is discouraged, but Female Occupant of No. 71 knows too much to surrender now.
What does she know?