I can really tell that the overall writing quality of the story so far has been improved a lot.  Especially regarding the sexy scenes.  This is like another sundae on top of a sundae which already had a cherry on top ;)

So yes as far as getting a fresh view on the world in addition to remembering a good story, you scored extremly well so far in my opinion.  I really appreciate the extra details/aspects/mini scenes and it makes every new chapter quite exciting to read in every possible sense.

I am not really great at orienting my reviews towards writing skills, as in grammar etc, but I think I might have one important suggestion (of which you probably already gave some thought but anyway...)

SPOILER : If you are reading this story for the first time and just peeking at this review, stop reading because I am about to spoil a part of the story !

In my personnal experience, the part where Melanie gulps down david was probably the most fantastic, expected and great moment.  I think as a reader you somehow get related to David from his perspective pretty closely and come to expect that moment as much as he does.  As such, I definitely think this moment should be THE scene where you add as much content, details, slow motion, etc etc as possible.  This is probably a very important moment of the story for most of your readers, so it would be nice to make it greater than great ! 

Don't get me wrong though, I already loved that moment enough to remember it very clearly, it's just that I see that part as a very good way to score as much as possible in terms of improving an already beyond awesome story !