October might be the month most-known for bringing out the undead, but hey, we've got A Christmas Carol that's full of ghosts. Zenit Miniatures had their successful Kickstarter campaign to bring the undead to Kensei. Now, those minis for the campaign are making their way to general release. As such, you can pick them up in the Zenit Miniatures webshop.
Now, not being an expert in Japanese folklore, I don't know if these are representative of actual demons/spirits or just cool-looking models. I will say that they are cool-looking models. Taisho, in particular, I think looks good. You can pick up him or Tenome (and ask him about his feast?). There's also two units, the zombie-like Dora-ta-bo and the undead dogs, Ukuri Inu.
All of these are available now.