Class 1-D Edit
Maya is one of Satsuki's friends in Class 1-D.
The two girls can often be seen interacting with each other and getting along very well. They once united to stand up for Kei in the survival test after her underwear was stolen from and both accuse the boys.
Kei is one of Satsuki's friends in class 1-D. The two can often be seen interacting with each other in the anime and getting along very well.
During the survival test, Satsuki was among the many girls that took up for Kei after her underwear was stolen.
There is no direct interaction between them in the anime.
Kanji saved Satsuki who was waiting for her friends to return from the toilet from two senior students, but indirectly also bad mouthed Satsuki. These two events should have already pushed the anger of Satsuki to her limit, but instead she directed it towards her overdue friends returning from the toilet and defended Kanji.