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Do BA students have parents? Do they even know what a mother is? Or do they spontaneously generate at school "age" and vaporize on graduation?

Arcana55 said in comment #2617875:

Do BA students have parents? Do they even know what a mother is? Or do they spontaneously generate at school "age" and vaporize on graduation?

I'm not all that deep in the lore, but I know at least Nonomi has parents.

Arcana55 said in comment #2617875:

Do BA students have parents? Do they even know what a mother is? Or do they spontaneously generate at school "age" and vaporize on graduation?

They're mentioned but never shown for one of the characters, and I believe that is partly to maintain the game's appeal.

Volume EX spoilers
The current "Academy City" setting is a "texture" over the students' "true forms" and the true nature of the world. In a oversimplified manner, the current Kivotos could be seen as "fake". Characters have been shown to age (we see Hoshino as a 1st and 2nd year student in flashbacks), and we also have mentions of students being childhood friends.

Volume 1 Chapter 3 spoilers
The information we have on "graduation" is vague, but if the Thunder Emperor is anything to go by it completely removes a student from Kivotos.

Arcana55 said in comment #2617875:

Do BA students have parents? Do they even know what a mother is? Or do they spontaneously generate at school "age" and vaporize on graduation?

Well, aside from the above comments, I'd imagine that Kei, specifically, wouldn't have parents in the traditional sense (and nor would Aris, for that matter). They may know what a mother is, but their knowledge would be all theory and no practice, I'm guessing.

Alanis, killed by a schoolgirl named Kei

Arcana55 said in comment #2617875:

Do BA students have parents? Do they even know what a mother is? Or do they spontaneously generate at school "age" and vaporize on graduation?

Besides what's already been said, there are occasional throwaway lines that imply the existence of parents, e.g. Midori mentioning "sharing a womb" with her twin sister Momoi. However,

Blank_User said in comment #2617877:

I'm not all that deep in the lore, but I know at least Nonomi has parents.

It's never actually stated specifically that Nonomi, or anyone else, has parents. Only that she's heir to the highly influential Saint Nephthys company. No actual family members are ever shown or mentioned, only an unnamed robot butler that is suggested to act as her surrogate guardian.

Similarly, Yukari is stated to be a member of the prestigious Kadenokouji family, but no direct family members are ever shown or mentioned. Only servants, and the former Kadenokouji miko Kokuriko (Blue Archive), whose exact relation to Yukari hasn't been stated yet.