The title is a wordplay. It can mean “tail-driven” as well as “thinking with the genitals” in german.
Next planned steps:
-giving him some yellow stubby teeth
-lots of work to do on the skin (wrinkles, warts, a wetmap, horny yellow toe nails, maybe even some hair here and there?)
-hair for the angel?
-better defined feathers
-the thingy at his butt is just a placeholder. Will have to model some metal/leather object that catches light a bit better than this one.
-motion blurr at the fawning tail?
-there’s also a huge cage with volumetric fog in the background, but it renders so slow that we needn’t be prepared to see the result
within this century. And also it changes the distribution of bright/dark contrasts dramatically. And actually i like the darkness. It represents
the vast void, where the ideas live. The theatre of thoughts, each one on its own stage, drifting as a bubble inside the vast.
-maybe some sort of godrays coming from the right?
looks like something out of a hyronymous bosch painting. 
Very interesting.
I’m not super fan of the lighting and there is a bit too much glossiness in the mouth I believe.
The ground could have much more variation.
…but overhall is very interesting and uncommon, I’m eager to see it evolving.
+1 to Modron about Bosch influence here.
Haha keep working on it. Could be really good. Though the feet look a bit too odd to me.