|Anime debut||Episode 13|
|Manga debut||Chapter 32|
|English Voice||Sara Ornelas|
Keiko is a middle aged woman with short brown hair, brown eyes and wears a red sweater. She has a wrinkled face and wears a pair of spectacles. In the manga she is much younger.
She seems to be a patient and kind woman, as she was seen smiling even as the child was crying. Although she was disturbed, when she watched Reiko make the child shut up.
Keiko is first seen carrying the crying baby, she is walking around the house and annouces to the child when Reiko comes home. Keiko is then unsettled as she watched Reiko makes her child cease crying. She quickly grabs her things and leaves.