Thread:RyuuSkarWolfingston/@comment-5899010-20121231225848/@comment-26228073-20130101051745

Well, some of them are just sealed in them. Ex: Shikigami Pipe Fox!, (throws paper), POOF, (Pipe Fox appears). (Calls back), Pipe Fox turns into paper.

And some are created by humans, which are those paper dolls.

Shikigami are kinda like slaves. You just sort of have to convince the youkai to become your shikigami, but then you will have to supply them your own power, like in Rozen Maiden. Even humans can be made into shikigami, but they will have to turn into youkai first.