Hey navigator… or can I say Katie? I find it confusing calling you navigator… anyway lol.
You’ve taken a cool approach regarding your demon! I like the idea behind the leg, though I think you need to give him a skeleton of some sort. What I mean by that is that the way I see him, he seems soft and squishy, like an octopus. Giving him a structure would make him much more solid I think.
Other than that… cool concept! 
I agree with DefiledVisions, that the character seems very vulnerable.



And second , I like your creature design but if I can suggest something…I would say that the first image (square 



