User blog comment:Godisme/San'ou/@comment-44061-20120725184708/@comment-5332138-20120726104253

They absorb spirit particles. Unless Kido is made out of a completely different substance then it's a pretty safe assumption.

How is the fear thing even a joke? It was mentioned in the manga and Byakuya even had a mental image of Rukia disintegrating. Why are disregarding it?

Not every bit of information has to be spoonfed.