So an inconsistency I've realised is that Liam shouldn't be angry or hold a grudge about his past life anymore - we've been shown that when the demon feeds on the negative emotions, he essentially purifies the people he does it to. He fattened up Liam's past life with misery, sure, but then he must have fed on him at the end.
So why is Liam still bent up over his past life and reacting to it?
I suppose we could say that he's just fulfilling his dying wishes (of being an evil villain), rather than holding a grudge?