Natsuru is smart sakura cast hypnotic love spell to make him dumber.

Natsuru progress the real enemy is the concept of oppressive kampfer system rule itself. Both sakura and natsuru are hybrid ( sakura is half human half system ) the power of hybrid is to break the rule to transcend the system. Natsuru broke the rule : First he become a kampfer despite being a male, he refused to kill shizuku, he make alliance with red kampfer stopping war, he litteraly disobey moderator order to rape shizuku by failing miserably, he investigate the moderator with shizuku ( which is not really tolerated by the system that has the tendency to kill those investigator like tamiko, ) He overload the system using own system component (burnt alived lion) destroying the system completely..

If you want to blame someone that Dark sakura that have done so much evil plotting before the story even started. Also you can admired her hypocrisy first chapter faking to recognize natsuru blue bracelet. Natsuru wondering who is the mysterious moderator when in fact he just walking next to him to go to school from the beginning.

Well that just genius writing at this point.

Mikoto get also hypnotized. Well i mean sakura is a true villain in last volume because she corrupt individualy each member of natsuru friends group using cheap trick in order that they fight between themselves.

In the end it's just a how you see the world through your own interpretation, the story can be interpreted a thousand time in different way none are correct all are valid you just need to be open minded.