>>53080856Miyabi is closest with Temma and Aruran, but Temma in particular is his best friend and are well known as a pair called Hanakishi. But those three collab often as a group called Yurustars.
Astel and Izuru are also best friends, and well known as the kusogaki duo who usually bully Aruran (but anyone's free game). In their high school drama CD they were portrayed as brothers to give you another idea of how close they are, Izuru has also said they have the image of siblings.
Rikka is close with Aruran and Shien, but lately more so Shien, but I don't watch them enough to tell you about their dynamic.
Roberu is hard to say, he's a bit of a loner and his most well-known pair is Babudon with Shien, but I'm not sure I'd say he's closest to Shien. He "gets along" best with probably Oga or just his genmates, he often plays the tsukkomi to everyone's antics.
Uproar all seem to be closer to each other than any of their senpai, but Fuma in particular is a genuine big fan of Astel.
