The Hakobake and Motobake

There are hundreds upon hundreds of yokai out there and many onmyoji cant keep all the yokai they have captured in their pockets so they keep them in hakobake and/or motobake. Much like the cards they contain they eventually develop eyes and mouths, no one knows why but one theory is about the same as how the hanofuda get them except instead of the energy coming from a talisman being placed inside of it, it comes from a large concentration of hanofuda cards in them which I guess in a way is still the same thing but whatever. made 4-3-2021