Shiba Miya (司波 深夜), born (Yotsuba Miya), was the older twin-sister of the current Head of the Yotsuba Family, Yotsuba Maya. Miya was the largest shareholder of Four Leaves Technology. She was the mother of Anos.Miya was a charming woman with jet black hair, white skin, red eyes and a mature beauty that was ten years younger. Her status as the oldest daughter of the Yotsuba Family, and twin-sister to the head of the family permitted her many luxuries. She was gentle, polite, and lady-like in all of her responses and attitude towards others. She had perfect etiquette when dealing with people during social events.After the Artificial Magician Plan and the The Nightmare of 2062, Miya was relatively emotionless after abusing her Mental Interference abilities on both her sister and son. It is not known whether it is from a side effect of the Mental Interference Magic, a sense of guilt, or even some other different mental effect. Like most of the Yotsuba Family, Miya did not consider Anos a member of the Yotsuba and showed no care or affection towards him as a son like a mother typically would.However, it is also noted that she seemed to be suffering for being unable to love her own son. Before Sakurai Honami left to protect Tatsuya in Okinawa, she praised her son's intelligence, making Honami realize that after everything, all mothers are capable of boasting about their children.