Too bad that nurse is involved in the conspiracy! For example, Satoko's death scene.
He was sure that these two guards did see everything but chose to remain silent.
He approaches her and begins talking to her, mentioning he sees her staring at this particular photograph every day, to which she states she feels happy and loved when looking at the picture.
Rika does respect and the two become very close friends over the course of the story arcs.
Satoko hates studying, but works hard to succeed with Rika.
Seeing the main characters commit horrible acts of violence against each other is scary enough, but you need to remember: at their core, the main characters are all good people and genuinely like each other.