>>53090745Mmmm that's a tough one, one would assume Fubuki it's the obvious option but besides them knowing eachother on Highschool there wasn't really any other mentions about their past together, I guess you could say Subaru because, interestingly, she isn't really motherly with her and often tease her so you could say they're close enough. Outside that no other name comes to my head really. Mio usually hangs out with everyone and she doesn't collab that much outside OKFAMS, she doesn't even collab that much when you think about.
Ah, she hosts The Holosport festival with Miko, so they must have some kind of friendship