Lingering Crimson (Season 2, Episode 13)

Lingering Crimson is the twelfth episode of Mushishi Zoku Shou.

Summary
An old woman has a troublesome habit of wandering into the nearby woods at sunset, declaring that she needed to return home. Her concerned husband reveals that she has no memories of her childhood and had arrived at their village in an eerie fashion, appearing on the same day another child had gone missing.