Looks great, good choice for the photo of the girl (did you take that or find that somewhere? )
That said, the creature, while well modeled and rendered, doesn’t really seem to be as well tied into the scene as I think it could be. Mainly because it is not humanoid, it is harder to read things such as size and body language. The former is causing some confusion for me as to his placement – is he next to her or behind her? This additionally lends a question as to the story in the scene – I am unsure if the creature is something that is fearful for the girl, or somehow a projection of her rage at something off camera.
I think this is a difficult challenge compositionally, actually, since a floating creature has no natural way of being grounded in the scene. Perhaps a stronger use of depth of field effects could help clue me in to your intent. Or, maybe some other method of grounding the creature to the world.
Also, the creature itself is disgusting and mean looking, but seems to be floating there casually. I can almost as easily imagine it laughing or spouting a comical quip as I can imagine it roaring. The anatomical choices for it have, I think, limited your options, but another crack at posing it might tie things together a bit. For example, the limbs should perhaps be reaching toward the girl or dangling behind to suggest a recent leap toward her. Also its eyes seem to me to be looking up and to the right, above the girl, and not focused on her if that was your intent.
Anyway, I think the hard work is done on this so far, and there’s a lot going for it, just a few composition tweaks in my opinion and it could be really great