I say "most likely" for Kaorin because there's moment where she tries to deflect when asked if she was gay, and insists that she's more Sakaki-sexual for the time being. Of course, there's a big difference between the teenage girl crush like she insists she has, and her actual behavior where she imagines wedding bells and rainbow flowers when chosen to dance with Sakaki or the intense jealousy she gets from any insinuation that one of the other girls slept next to Sakaki.
Not minding if Sakaki was a guy is one clue-in towards bi, but, again, her emotional investment to Sakaki is too passionate to really go 100% exclusively straight attraction if it never works out for her.