Well the image is a bit disturbing to me. But what is art if it doesn't create or evoke a strong emotion, right?
I think the sketching looks good, although I am not an artist, and can't give you any technical feedback. I can say that my eye is drawn to the hands, rather than the dog, which may be your intent. The bottom right corner, which is full of the dog's head, seems a bit bare to me. And especially since you're thinking of "torn flesh" (ugh!) you might want more expression in the dog's face or eye. I guess the dog does not seem vicious, is what I'm trying to say....maybe more of a snarl, more teeth showing, and maybe a bit of a squint in or around the eyes. More so if it is a wolf rather than domestic dog. It looks more like a lab or shepard playing with a toy, than a fierce wild animal......which also may be your intent, I'm not sure. Anyway, that's my first impression. Nice work