Midou decided to bet everything on MC and now that something went wrong is MC's fault, Midou regressed in character development ala kouki from arifureta
@aasegovia88 Midou also has unreal expectations in thinking nobody on his side would ever get hurt or die. Also, MC never betrayed them like Midou is implying by saying he can't trust MC. That was the best possible plan. Their friend died and it is tragic, but that's no reason not to trust the MC.
@Tenzai i think midou thinking is fonunded...... he doesnt distrust the mc beacuse "he's a heartless person" but rather beacuse he suspects (and its right) that the mc will have no problems with using them as pawns if it means that they could defeat the demon lord..... basically he thinks that if there's 2 paths one where the demon lord is defeated in 10 years and one where 20% of the team dies but the demon lord is defeated in 1 year the mc would chose the second path.....
why do i say that its right? beacuse we have already seen the mc using his classmates as bait.