I have tried repeatedly to draw a picture of both of his forms that I was happy with for awhile now and it finally worked out. This is another long running OC of mine who has gone through a zillion names and backstories.
As of right now the key part of his backstory is if you're skilled enough in occult magics you can go from "being used a human sacrifice to summon a manticore demon" to "stealing the power of said demon while only dying a little bit"