At around 13 minutes into episode 7 of Fate/kalied liner Prisma Illya 2wei!, when Illya's mother Irisviel talked about the power of an older sister, there are a few characters appearing in the background.
To quote Irisviel:
Older sister. Yes, that is the one who is older and has more power. When it comes to domestic hierarchies, they can hold more power than even the father. And they have absolute sway over younger siblings, which can never be overturned. The quote one great man, "No little sister is superior to her older sister!"
Who are these characters? And how does these characters compliements her argument about the power of an older sister?