Portrait of a guy who hates his job.
The thing on his head IS in fact his head. It's like a vestigial fin or something. He's actually a pretty unique mix of a bunch of different kinds of aliens, but that means he's inherited some features that don't really serve a purpose and just get in the way :^|. But the skin along his jaw is extremely hard and boney, which is actually very useful in a job that makes people want to punch you all the time.