Kallen's Mother (カレンの母)
She's a Japanese woman who works as a maid in the house of Kallen's father to be close to her daughter.
Animeography
Code Geass: Hangyaku no Lelouch
Code Geass: Hangyaku no Lelouch R2
Code Geass: Hangyaku no Lelouch R2 Special Edition - Zero Requiem