Gekka, early 30's.
Introduced as a kind & loving mother figure, Gekka is also a renowned AR developer and feared anti-institution revolutionary. She's a strict teacher, hard to impress, has a sharp tongue and doesn't tolerate weakness. She got along well with the family when they were younger but after disappearing for 5 years, she resurfaces only to find Don is obsessed with her and Lona is deeply resentful of her disappearance.