They are fine. 🙂

However could they be more muscular with somewhat more pronounced muscles and muscle tones or at least some skin tones to that end ?

The way they are at the moment, they feel a bit too “normal” to me , as in not too “monstrous” or “scary” or even simply “Supernatural”; especially since they are meant not to wear any clothes most of the time. I believe more prominent muscles should be a way around that. 🙂

Maybe some kinds of tight fitting auras could be other ways to do the trick too.