She had done it as a plan.

Coldly, carefully, over weeks.

She had bought the box.

She had chosen its size, understanding exactly what that size was for.

She had cut the cake with steady hands and handed poison to children who loved her, and then she had stood over us in the grass with her arms folded and watched us fall, and felt, by every account, nothing but satisfaction.

I have tried, and failed, to locate the place inside a human being where that becomes possible.