We know that animals in Bleach died and can become Spirits or Hollow right? I just wonder what happen to an animal that go to Soul Society? Since because of Kukkapūro's backstory we know about animals become hollows and how they live.
Also in the first filler episode the cat Raku seem to have the power to turn into a powerful Spirit animal? You think other animals are able to do that? I think that a very interesting idea to see a bit more of.