Very nice design. I daresay it's almost cute, if not for the murderous gleam in his eye! ^^
I love the pose especially. I think you really captured the moment of him leaping towards an enemy with intent to strike him down.
Adding to what others have said previously about how "rat-like" the image is (and i appreciate this is rather late in coming), I think it's the unusual fur colour and pattern that might throw viewers off. I like it though, I was still able to look at this and immediately recognise that it was meant to be a rat person.