These girls have been through so much existential horror over the course of this summer vacation that when they get hit with the revelation that they've spent their lives surrounded by robots disguised as people and that their teacher is one of them they just go "Huh. Neat."
Also, that cloning machine that Raimon used to make a new body for Yoki is probably fringe science, and Yoki has repeatedly been shown to be either resistant or immune to fringe science, so... Dowman, are you foreshadowing something?