* Ichika almost killing someone with flower petals.
* The nature of [[spoiler: Ichika's test.]] She eventually has to decide [[spoiler: whether to kill herself or the rest of humanity.]]
** Even worse is the admission that such tests will happen again to others, who will be given the same choice. And if they refuse, [[spoiler: they die.]]
* Saya's scarf. [[spoiler: It's actually a scythe.]]
* Souma [[spoiler: turning to stone for breaking the rules.]]