I think there’s two approaches to this.
- Tooru plants the rock insect to kill Rai’s father for some petty/unimportant intention. The calamity still flowed to Rai and his mother.
- Tooru plants the rock insect for an unknown reason to kill Rai’s father and uses WOU’s calamity to kill his mother. Possibly because they know/do something important for the locacaca trade.















