Jakob is an incubus with an empathic affinity for lust (and fear), so occasionally he'll... let go. This is what he can look like when he lets his hair down.

This was a speedpaint commission from ladychimaera on FA, it's amazingly good, but I'm not sure if they still have slots (if anybody wants one of their own).
I'll link to their original as and when it's posted to FA.