I think Natsume Yuujinchou would count. Though, they are yokai so they aren't wanyama but purely Supernatural beings. This is Nyanko-sensei in his cat form. He is actually a powerful yokai named Madara and can transform himself so I'm not too sure if it counts au not.
There are also other yokai au 'spirits' that come from snow, a statue, a chai cup, a sparrow, and even a mirror.
This is technically not an anime, having not yet been animated, but it's a pretty rockin' web comic. Though it's American made, it has a heavy anime base to it, and wewe can tell that this was inspired kwa anime. ^-^