Youkai from touhou seem rather voidy. Not only they are born from legends and mythos, they are directly related to fear of unknown. If fact, their existence depends on humans never trying to see what is really hiden behind the phenomena. Youkai tend to die out when the phenomena is actually explained. But then they are also somewhat hopey. Hope+Void?

I don’t think I know enough about Youkai to properly pin-point them down like that, they could also be Heart I feel? But yeah.